My understanding was that for non-deco dives, reverse profiles aren't considered particularly risky. Obviously, this was a deco dive, so it may not apply, but the amount of stops was pretty minimal and I had my computer set relatively conservatively.
(Here is a random DAN article I found on it:
https://www.dansa.org/blog/2015/01/2...e-it-backwards)
However, it does add to the risk a bit. I was on air rather than 32%, as the dive centre was low on its Js of O2. I also had quite a lot to drink the previous night, and I was a bit dehydrated. So there were a few minor risk factors, and unfortunately they all aligned that day.
The major risk factor was having a PFO, of course, and exercising after the dive. (My tanks are steel, so a full twinset and kit is about 50 kgs, So walking it up a hill is not a trivial task.) It was about my 300th dive, and I know quite a few people who have PFOs who managed 100s of dives before getting bent and finding the bad news.
I dived Mexico once (the Soccorro Islands rather than Cozumel.) I really liked it, it would be nice to go back. The cenotes look fun.