You need more than just sit there hose documents. U visas take years if you do everything correctly. If you make mistakes it will take even longer...

What is the best way for my non-citizen wife to apply for legal residence ?

You are asking good questions but the answers vary from couple to couple. You need to speak with a lawyer BEFORE you get married

Technically, anyone who has not previously participated in PTI is eligible for PTI. Realistically, there's almost no chance.

Re-Entry Permit impact on Citizenship ?

A reentry permit has no effect on eligibility for citizenship. It affects only your ability to re-enter the U.S.

What will happen now?

You go back to face the charges from the beginning. All outcomes that were possible before are still possible. Hire a lawyer--maybe you can...

It is a felony. Usually a lawyer is more reliable than "online".

Can send my fiancee a visit to me and his kids?

Your fiance can apply for a visitor visa. You are not part of the process and your involvement would make it LESS likely he gets the visa.

Hire a lawyer. That's really the only thing you can do.

I’m going to turn 18 in 6 months, can my mom still file for my u.s passport or is it too late ?

You are asking good questions, but you need to consult with a lawyer to review the details. This cannot be answered based on the information...

What can I do I know this is illegal or something I should be able to fail something or get someone in trouble or something?

If ever there was a good reason to hire a lawyer, this sounds like it.