As everyone above already stated, yes you can stay until your case has been adjudicated. However, it is to your disadvantage if you wait and waste time after you have received your marriage certificate file immediately
Bring your GC with you, enter with your esta and be prepared to answer questions. When you left permanently in 2019, did you notify immigration or anyother relevant authority ?
At least now you have an idea of what could be amiss. If you have a copy of your divorce decree, hold on to it as they might ask for it even though you submitted it before.
If the situation cannot be helped, my advice is that you have waited all this while for this, You cannot afford to have it messed up....talk to your HR see if they can do something about your work trip.
Do not forget to foward your mails to your new address with USPS.https://www.usps.com/manage/forward.htm, it might take a while for USCIS to effect your address change....meanwhile they will be sending correspondence to your old address. This has messed up alot of immigration cases...AVOID IT AT ALL COST