SalSterling

After submitting the application then there is option to submit any supporting documents that applicant wishes to provide and there your father in law can provide a simple letter to the consulate officer about this business, and supporting documents which proves that he owns that business, tax returns, bank statement for last 6 months. Most important is the purpose of his visit. If he is a successful and a busy businessman then he barely have 1 or 2 weeks to take off from his business and if he mentions he is going for few months then there will be more questions.
Most businessmen get the B1/B2 by providing their on going relationship with their clients in US or if they are a client of a US business or going to attend a conference / exhibition in Vegas or wherever belongs to the industry applicant belongs and there must be some sort of registration with that conference to prove. 
 
Thank you.

After submitting the application then there is option to submit any supporting documents that applicant wishes to provide and there your father in law can provide a simple letter to the consulate officer about this business, and supporting documents which proves that he owns that business, tax returns, bank statement for last 6 months. Most important is the purpose of his visit. If he is a successful and a busy businessman then he barely have 1 or 2 weeks to take off from his business and if he mentions he is going for few months then there will be more questions.
Most businessmen get the B1/B2 by providing their on going relationship with their clients in US or if they are a client of a US business or going to attend a conference / exhibition in Vegas or wherever belongs to the industry applicant belongs and there must be some sort of registration with that conference to prove. 
 
Thank you.

Simply put, you subtract the time period between priority date and approval date (date on the i797 approval notice) from the age of the person. If this puts their adjusted age under 21 when the priority date is current they are eligible for a visa.  So for example if someone is 24 but it took 5 years for uscis to approve the petition, their CSPA adjusted age is 19 and they would be eligible for a visa. They have to remain unmarried though.

I think Officer at the airport was not well informed. An approved petition will expire on expiration date that mentioned on the NOA2 only if there is no actions were taken by the petitioner and beneficiary once NVC made the contact. In your case and any other cases where there is an approved visa then there shouldn't be reason for not allowing your to travel.
I am writing this with my personal experience since one of such petition was expired that I filed and we didn't take any action since we were not ready at that time etc.
I hope this matter will resolve quickly and you can join your fiance.

@KristineGB Oh, I am doing great and I am glad that my EX unable to get the green card and had to leave US. Sometimes, I just feel like to love Donald Trump  who made it impossible for anyone who try to deceives a US citizen or the laws of US immigration, but I am so very mean that I am still not going to vote for him  

Please make sure to return within 180 days. My mother just came back couple days ago after over staying 180 days but they stopped her at the airport and she had to wait 4 hours to see the officer who revoked her greencard but gave entry subject to Immigration Courts decision and now we have to hire an attorney and prepare a case so she can get her greencard back.
These days all the immigration laws are enforced so make sure to return within 180 days.

Please make sure to return within 180 days. My mother just came back couple days ago after over staying 180 days but they stopped her at the airport and she had to wait 4 hours to see the officer who revoked her greencard but gave entry subject to Immigration Courts decision and now we have to hire an attorney and prepare a case so she can get her greencard back.
These days all the immigration laws are enforced so make sure to return within 180 days.

Please make sure to return within 180 days. My mother just came back couple days ago after over staying 180 days but they stopped her at the airport and she had to wait 4 hours to see the officer who revoked her greencard but gave entry subject to Immigration Courts decision and now we have to hire an attorney and prepare a case so she can get her greencard back.
These days all the immigration laws are enforced so make sure to return within 180 days.

I came across someone who was in the same situation as yourself and able to come under the same preference even after his 22nd. birthday. I know they hire an attorney. It will be tough to locate him but I will try and see.

As far as my information there is a provision in USCIS rules which says if beneficiary is turning 21 within next few months (12 or so) from the date once the visa become available at NVC (not from the time USCIS approved the petition) then beneficiary will get the visa under the same preference. Please make to consult with an immigration attorney so you can get benefit from this rule in case your visa number (nvc case number) becomes available before your 21st birthday.

CLARIFICATION: I apologize for providing wrong information related to 'Letter of Intend' because I wrongly comprehended the advise from my friend. He said 'I don't need to write a supplement for the question related to 'How We Met', but somehow I thought it was related to 'Letter of Intend' since I called him about it but somehow I totally misunderstood him and made a post here that if there is no letter of intend then not to worry since it is covered in the latest I-129F form.
Thanks all of you who noticed the error. Special thanks to KayDeeCee