My office does not generally file an I-864 with an employment based adjustment of status application.

It is a problem to enter on one kind of visa with an intent to change status to a different type of visa upon one's admission.

If the consulate sent your visa for revocation, and CIS reaffirmed it, and they are now considering it again, then you are correct. Similarly if...

Generally if a person was lawfully admitted into the U.S. they are eligible for adjustment of status based on marriage to a U.S. citizen.

You should send it to wherever the application is currently pending, either the service center or your local USCIS.

It is very possible. And it is also possible the employer wants to try to prevent you from porting to a new employer.

Terrible! I have not seen that there is any publicly known rule about what will disqualify a person or when they can reapply.

You can refile anytime you wish. There is no rule that you have to wait any certain amount of time to refile an N-400 that you withdraw.

You do not need to cancel it but if you really wish to do so, simply notify USCIS you wish to withdraw the application and you are leaving the...

You cannot return to the U.S. without advance parole or some other document that allows you to be admitted or paroled.