Coco8

She still has a passport from Cameroon and was denied immigration visa. She is only studying and working in Canada, so I'm assuming she has a visa. She still needs a visa to travel to the US and she is going to have a very difficult time getting a visitor visa. She'll be denied because she already has another visa denial, she has no strong ties to Cameroon (or Canada), and consulate in Canada is particularly difficult. You should visit her in Canada. At least it's closer. If you are eligible for a TN visa, you could go to work in Canada and live wherever she is studying and working. You might also be able to get a dependent visa from her Canadian visa.

If it's truly a top school and a very competitive program you could get lucky with F1. I do know someone in your situation who did got the F1, but it was an Ivy league school for a Ph.D. program with full scholarship & fellowship. You could try. However, I recommend asking the program if you can defer until next year. In a way, to start a program you have to be in the right mind frame and it could be a very big move (start classes, new home, moving in with your partner), plus having to go through AOS. It might be too much and distract from your studies.

I wouldn't travel. When you come back with OPT you get a lot of questions because you are in a weird position (not a student but not a work permit). You are entirely at the disposal of the CBP agent. I've had friends that had problems and you are also at the end of your OPT with an H1B approved. Either check if you can get your visa stamp and enter 10 days before October 1 (the day of your first day on H1B), or postpone the trip. FYI some countries have long delays for appointment while others don't.

Employers don't do an L1 to let you go a few months later. L1 is expensive because they have to hire a lawyer. You also have experience in your own company. My partner had an L1 and the size of his application was like a heavy book. He didn't do anything; the lawyers mailed by FEDEX all the paperwork. You have a great opportunity. Like others said, you can do AOS while you are in the US with the L1 and your application will continue it's course. L1 will make your transition much smoother. Make sure you get paid for relocation and all of that.

Send an email to the consulate. He might get lucky and get a July appointment. From experience (but not in UK), you get a very quick turn around with an F1; less than a week and you get your passport back. He won't be able to enter the US very early on the F1 visa. Only 30 days before the start of the fall semester. You can, though, visit on ESTA much earlier to make arrangements of where to live. The important reason to try to get an earlier appointment is to be able to get settled and also, universities have special days on campus to get a social security number. The best is to do it on campus because otherwise, he'll have to get someone to take him to the worst area in town to get one. He doesn't want to miss that day.

No, you only have the HHR ONCE.

Having sick parents is not a strong tie.

Unless you get married, it's very difficult. In addition to the other options people have given, if you are currently working for a multinational company with US presence, they can transfer you to the US with an L1 visa. If you have a good career + education + work experience, but it's really hard unless you are a software engineer with some contacts or something like that.

Like where? This is not true. You can also do a graduate degree in your country and meet your GF somewhere else for a holiday. Get a good job that's related to what you want to do. Also, where is your program in the US? What place on the ranking does this university have? I think you should ask your program to be postponed for a year, but only if it's a good university. If this is a shady university or too low ranked, you don't have a chance to get a visa next year. And choosing a university based on location is just dumb. You also say you want to do an MBA. What does have to do with working at Mercedes Benz? Education programs that make no sense with your previous experience or goals are not going to get you an F1 visa. People usually need a few years of experience before doing an MBA because it is useless for people who just graduated from undergrad. So that's already a red flag in terms of the ranking of the program. Quora is a mess and lots of misinformation there. I don't know why you are reading that. Your big issue was giving information that did not answer the questions when you traveled to the US. You gave too much unnecessary information. Also, I'm guessing you traveled way too soon after your exchange problem. You have to space visa applications and travel way more.

If he has a tourist visa he can visit to get married and then leave. Or he can visit after you get married through Utah. You can also marry through Utah and meet in Mexico if you don't want to risk a trip to the US.