Just wanted to provide an update on my case. Passport picked up today, with visa approved. Some notes I've collected for this great forum that avoided the need for any consultant or lawyer to get through it...
Thanks to @From_CAN_2_US for his thorough list of documents to bring to the interview. Didn't end of needing more than what was listed on official websites, but good piece of mind.
Do as much of the medical BEFORE the actual medical. What I mean is, get all your shots not long after being DQ'd. In our case, it was mostly boosters. Some shots require 2 rounds, several weeks apart. The medical process for us, was a complete cakewalk by being prepared. The Dr. even commended our preparedness.
Denial of Entry to the US during COVID lockdowns, even though officially known as "Withdrawn", is still a Denial of Entry. If this happened to you as it did for my immigrating spouse, go file a FOIA request to at least get the document/evidence showing this incident. Answer honestly on the DS-260. The officer will confirm this info, but honesty seems to be the best policy.
You CAN "delay" the overall visa process. In our case, we wanted to wait a bit before leaving Canada. After the I-130 was approved, we waited about 8-9 months before submitting the DS-260. No issue doing that.
Montreal is a great city for food, budget some time ahead of the interview if you can, to enjoy what it offers, even when it's freezing out. Book a hotel within a 15-20 minute walk of the consulate to avoid needing cabs.
We will cross sometime later this month via US-preclearance at YYZ. Good luck to the remainder of you!