Yes, your husband's employer can file an H4 extension while your application for change of status is pending. They probably will not send an RFE...

Could be a mistake. Could be you have been recommended for approval but your case is on hold. There is no way to know.

An interview on the asylum application? On the I-140/485? Are you a U.S. citizen, perhaps you have considered filing for him? See a lawyer.

Yes, if you are married, you should indicate as such with your consular processing forms. Especially if you want your spouse to immigrate with you.

I am not aware of any immigration related penalty for taking money out early from one's retirement account.

I am not aware of any immigration penalty for taking an early withdrawal from one's retirement account.

I am not aware that taking money from your IRA account for medical needs is a basis to deny naturalization, or is a sign that a person lacks good...

Since USCIS refuses to take your payment you have little choice but to wait for them to notify you to pay.

Since it was before your adjustment of status, it may not matter, perhaps you were a minor and they found you did not have a mental capacity to...

You should be able to port under AC21 to a new employer. A new employer can substitute for the existing one, also under AC21.