No, they cannot void your green card. The only way you can have your status removed is if CIS puts you in rescission proceedings, or removal...

Your wife can file for an H4 extension so long as she is in fact your wife.

No, the fact that you filed before is not a basis to expedite.

It depends, no doubt, on your status, and her status. Generally a U.S. citizen can petition for his or her spouse to become a permanent resident,...

Just keep following up. If no response by September 1st, find a lawyer to file a lawsuit to try to force them to make a decision.

You cannot work with your EAD based on OPT as an independent contractor [unless your DSO approves that]. Your pending TPS based EAD will qualify...

You are permitted to use any work permit you have to do any work that is authorized. Working, with permission, does not violate your F1 status. ...

There is no rule against a person with CPT to leave the U.S. and work abroad.

If you quit your OPT job, you are no longer in valid F1 status. You may wish to file for reinstatement, or try to change status.

OPT and CPT are both F1 statuses and if you are admitted for your OPT, you are admitted as an F1.