Chantal and Pedro. I don't see anything wrong with signing a pre-nup. It's not necessarily means that it should "protect" anybody's assets, it may just specify the conditions of future divorce if it ever takes place. US lawyers are not cheap, and if millions are not involved both husband and wife may end up bankrupt, and their lawyers end up getting wealthier. Yes, they do not have time to sign a prenup before wedding - but I don't see any problem sign a post-nup after wedding. And if Pedro decides not to sign one, Chantal can always hold onto applying for his green card - and in the end he will just have to go home, and she will get a divorce.
I don't think that Pedro has anything to lose by signing the agreement but he might a lot to win. If he is ambitions, he will take the opportunities this country offers him - and get education, and work hard, and eventually will be able to afford quite comfortable lifestyle. And if in 10-20-30 years they decide to divorce, he might be thankful for the fact that he signed the agreement, and they do not need to spend lots of $$$$$ and nerves and time on lawyers.
Anfisa and Jorge. Anfisa came on K-1 visa which means that she KNOWS exactly how much Jorge makes. She had all his tax returns for the last years with all numbers. Does she know how much he pays in taxes, bills etc.? Probably not. They have 13% flat tax rate in Russia (if I remember correctly). It doesn't matter what he promised her when he proposed, she knows that he can't give he more than he can.
They are in California, and after they get married (if, off course) his debt in marriage will become her debts, too. Not sure she understands it, and I dont' see Jorge explaining it to her.
Ticket back to Russia. I am sure that 99% of people coming to US from Russia have round trip ticket. Price for one way trip and round trip is the same (and ask me how I know that :)) or the difference is minimum. Changing the date is usually around $150. So I am sure that unless both are super stupid Anfisa has round trip ticket and can leave any time she wants. Uber is cheap, and I am sure she can afford it.
Nicole and Azan. I doubt she will be able to show enough income to file for K-1 visa, so she will need co-signer (one of relatives probably). I do like Azan but I am sure he is after green card. At the same time he probably realizes that living for 3+ years with Nicole are not going to be easy, so he is trying at least to encourage healthy lifestyle. I can't blame him. 3+ years come from the fact that it takes around a year to get the first green card and then another 2 years to get the second (permanent) one.