Great question. Be careful! None and N/A are not the same thing! Your question is a good example. The question certainly is applicable, and the government will consider N/A as not answering. On the other hand, if he does not have one, then none actually is an answer.
As of now the law requires you to be a permanent resident or citizen to serve in the armed forces. However, on January 29th a bill was introduced in the U.S. House of Representatives that would allow DACA's and others who are legally present to enlist. One great thing about the bill is that it would allow for DACA's who enlist to get a green card right away. So far it is not yet law, though. Stay tuned. The link has a place where you can click to show you support the bill.
That person is allowed to remain in the U.S. until there is a final decision on the application. The government has 90 days from filing to give him employment authorization--assuming you correctly applied for it at the same time you filed the I-130 and I-485. The Seattle district is fast on these cases. The person should have the interview 3-4 months after filing. In the meantime, that person is an adjustment applicant. No actual status, but allowed to be here.
She should be Ok, but be aware that iIf the government has reason to believe the marriage wasn't bona fide, and the case comes to their attention, they can initiate proceedings to rescind the green card even after the condition is removed. She should be careful to retain evidence the marriage was bona fide and what was going on that led to divorce just in case it comes up
I recommend you contact an attorney. The government does get suspicious when a U.S. citizen petitions for various foreign spouses, especially when not much time has passed in between. Apart from the potential proceedings to rescind your prior spouse's permanent residence, you could potentially be facing criminal charges of fraud, if you can't document the facts of the abuse. I highly recommend talking with an experienced attorney before doing anything, including before getting married again.
I'm sorry there isn't an easier way, but for now your best option is to hope for that H-1B. You should know soon. If you don't get it, then you should have an attorney evaluate your record to determine if you could do EB2 with NIW, but it does require a lot to qualify for that.
You do not need to wait to file. Correct, you would not apply for OPT. Once you have filed your adjustment of status packet, you will be allowed to remain in the U.S. until there is a final decision on your case. Obtaining a benefit based on the student visa, though, requires you to show you still have the intent to return home, and clearly once you've married a citizen and file for adjustment, you don't intend to return home. It doesn't matter, though, because you are correct that you will...