ricewanted

Yes, your brother may apply to renew his B1/B2 visa even if it was never used.  Like the first time he applied, approval is not guaranteed and mostly depends on his ties to home country as documented in his DS-160 form.
 

Not an inherent issue. He travels to the US with the tourist visa (and proof of return flight, ties back home, etc.) and if admitted CBP determines the I-94 end date which will be different than the visa expiration date. The date that matters once admitted is the I-94 date. https://travel.state.gov/content/travel/en/us-visas/visa-information-resources/visa-expiration-date.html

I'm not sure what happened to other posts about against the wedding in VN for a K-1. My case was OK and good with K-1 after a wedding in VN:
- Two years ago, we attempted to register cert of marriage license in Justice Dept - So Tu Phap (HoChiMinh), but they denied our application due to missing documents.** The missing docs were:
(I was divorced 10 yrs ago in US). Justice Dept - SoTuPhap HCM asked me to bring my divorce decree & have VN Embassy in US to translate Eng -> Vietnamese then get certified by VN Embassy in either DC or California (these Embassy staff asked $570 while Representative in Hanoi told me over the phone of $250, I sent the money order of $250 + $40 Certified Postage Fees, they took out the money, trashed my case after I refused paying more).
- Went back to HCM another time, swear & notarized in US Consulate at HCM for a Single Affidavit ($50/each stamp) & certified with So Ngoai Vu (VN Immigrations Office to certify (some $5 - $15 fees, can't remember exactly).
- Went back to Justice Dept SoTuPhap again, got denied again. But someone approached me & claimed they had "connections" & willing to get us "through" for some $. They asked how much I made and gave me a price in $USD.
- We went ahead get engaged & wedding in VN w/o license.
- We had to get married in VN because I only have 2 relatives in USA (hundreds of friends, but VN traditions only care about parents & relatives).
- Filed K-1. Explained the case with a typed letter attached to I-129F.
- 6 months later, K-1 interview & VISA in hand. Just be truth during interview, it's ok to be nervous (my fiance/wife said).
- Current in AOS: got married ceremony with my only 2 relatives & a small dinner bunch of friends & co-workers.
That's our case.

I'm not a Psychologist, Physician of any type. I'm a nurse. But I'd like to chime in to help. We are in NW btw. You might find your wife in same shoes, or differ somewhat. I'm a Vietnamese guy, we have a huge community of Vietnamese locals here: foods, shopping, markets all were either Vietnamese or Asians.
My wife in USA for months, but she still suffered depression, moods swings. She lost weight, was sick severe due to "homesick" (admitted to hospital). She cried in bathroom alone. She cried softly in her sleeps. Even if she didn't cry thru the night, I found her tears dried up on her face & pillow every other mornings.
I tried these: take her outdoors, hiking, walking together (always bring an umbrella regardless weather, water bottles & snacks in backpack), ride bicycles, take photos of her at random seconds w/my iphone, always standby/stand nearby the women restroom in malls/costco/walmarts/hiking trail/picnic areas/rest areas/parks...etc (regardless she has her phone in her pocket/purse or not), always offer foot/legs massages as she walks (she didn't use to walk a lot in VN, easily get sour muscles/tired....get her running shoes for walking as well).
Find out what she interested in, sometimes she fell in-love with big SALES in shopping malls, especially those with 50% SALES and higher. Brought her to thrift stores for treasures hunts, shown her websites about expensive & rare US coins, pennies, stamps, etc… to carry her interests. Brought her to 4D (D-Box theaters) or take her to those games center where racing or shooting but the seats shake heavily. Drove her around towns, downtowns where there were homeless, let her hand those homeless individuals (men/women) $1 & coins herself.
Arrange her to go to Hospital/Clinics for appointment, check up and go to those that have interpreter services (or staff speak Vietnamese). Get her Driving Instruction permit ASAP, teach her to drive patiently in remote parks, empty parking lots, and rural highways.
Takes her to funny cartoons movies (such as upcoming penguins movie) or romantic movies (avoid Terror, Horror or Too much Actions/Shootings/Killings/Deaths movies, because she couldn’t understand from listening, she only tried to understanding by stare at the images).
Hook up Facetime, Skype, Video Chat to let her talk/chat with her family in VN, voice phone alone is not sufficient, but if you think voice phone, try OneSuite or Localphone.com have lower rates for phone.
Got to to go now. But let me know if none of these ideas work for you or you are welcome to PM me at anytime.

Just an FYI. Visa On Arrival - for new travelers
I don't know about the increase in VISA fees.
I can't find it anywhere on the web of this recent increase.??
before I did the on-line "invitation letter"
i did call the Washington D.C. VN embassy for 1 month, 1 entry; i got different answers
1st call = $300
2nd call = $250
so i looked for alternatives since i knew it only cost $45 for a 1 month, 1 entry VISA.
VISA stamp cost at TSN Airport - HCMC at VISA office (as of December 2013)
1 month single - $45
3 months single - $45
1 month multiple - $65
3 months multiple - $95
My experience last year - multiple trips
before you fly:
1) USD money $45 - $95 for actual Vietnam VISA stamp, cost depending on how long you will be staying & number of entries
2) a pen
3) a couple 2"x2" passport photo
4) print out your "invitation to visit letter"
5) your passport
how to get your "invitation to visit letter"
various on-line services - the company is usually in US, need to check, some have Paypal = so safer alternative.
Service Fees:
a) cost = varies from $8 USD to $50, usually takes 2-3 days, cost more for RUSH or longer stay. different website companies = different service fees. example: you pay anywhere from a low $8 per person (fee schedule is listed in table) for 1 month – 1 entry
b) service: what you get for the fees = cost for an agent in Vietnam to go and apply and get you an invitation letter, only a letter to come to Vietnam with your name, passport number and date of visit (info from on-line form that you fill out). They will email you this letter in 2-4 days (varies) but not too long. The letter may have a few to many other people on there since the local agent in Vietnam goes and request this letter once daily. You can pay extra for a letter written just you and your group. This letter allows you to travel/fly to Vietnam. kinda like a pre-VISA letter. I used this service twice, 1st = 1-month single visit, 2nd 3-month multiple visit.

Process:
a) you fill out the on-line form
b) confirm the info
c) pay by credit card - the company is usually in US, need to check
d) they will confirm with an email
e) in 1-3 days, you will get an email with an attachment = your letter = approve for to get the VISA when you arrive at airport (TSN, hanoi or da nang) – your name will be listed among other people (they submit as a group in vietnam) or if you wish to do it as individual or small group = you can = just pay extra fee = private; but it is not big deal with the big list
- i usually print out 2 copies (1 with my passport and ticket, the other in my bag just in case) and bring with me to airport
=> see a copy example of what I received in my email -names & info have been blacked out for privacy - i can't seem to attach or paste it

f) at airport check-in and at all gate(s): you will NEED to show the airline representative this letter
- no letter = no travel, unless you already have a bonafide VN VISA to travel in which case ignore the rest :-)
g) arrive at airport in Vietnam
h) at TSN airport HCMC, follow the path to "immigration" then at the big hall, on the left side of the “VISA immigration checkpoint” is the VISA ON ARRIVAL window
i) Fill out form at the table against the wall
j) Get in line with the completed form + your VISA ON ARRIVAL LETTER + photo 2”x2” + your passport
k) give them above
l) they check it for a 10 - 15 minutes, longer if crowded
m) they call your name = pay $45 (1 month – 1 entry)
get VISA stamp sticker placed in your passport
n) go to VISA immigration checkpoint with your passport
o) ask a few questions while they scan your passport – get stamped
p) go to pick up luggage downstairs at carosel (don’t get help = $) unless you really need it, the luggage carts are free for you to use
q) go to custom with all your stuff – x-ray your luggage - have had no problems
r) done
no problems, no hidden moneys inside or under passport, no extra fees.
TAXI Cab = another story
"VISA Exemption":
here is the link to the ministry of foreign affairs on this matter.
http://mienthithucvk.mofa.gov.vn/Default.aspx?alias=mienthithucvk.mofa.gov.vn/en
as others have mentioned this. you can apply for this "VISA Exemption, a little booklet with your info & picture, last 5 years". It cost $40 for my cousin and $50 dollars for my sister, maybe $70 now ???, i will have to get this done and see on cost$. This is to make it easier for those who wish to travel to VN qualified under this path. I did not know about this last year. My cousins, sister and brother just got this. So, I will be getting this soon.

My fiancee completed interview on late Feb 2014 with these questions:
How did you met? (F: facebook, add friend, become friend, chat, talk, etc)
How many time(s) your fiance was married? (F: once).
Why did he divorce? (F: xx yy reason, issues started in 200x)
Do you remember the date he divorced? (F: he asked me to memorize the date, it is xx/xx/201x)
Why divorce in 201x instead 200x? (F: I don't know, he might have mentioned the reason but I can't recall at this time).
Overall my fiance said the officer is so friendly, nice & handsome & speak Vietnamese perfectly :-) By her descriptions, I think I might have met this officer during my previous trips to HCM consulate.

Hello I am very happy to tell you that our visa has been approved!!!! Originally we had a blue sheet due to my fiancee forgot her police report and 2 5x5 pictures. We came back in the same afternoon to give the two require materials. And we were issued our visa. I will submit my detail review in a few days. We are very busy to prepare everything for the departure.
Another positive note is that the immigrant visa chief came out to congrats us. We are the first same sex visa approval in Vietnam. She was asking if we are willing to share our story. Good luck to everyone that have interview! It is very positive to same sex couples.