I have rented gear from Zero Gravity in Puerto Aventuras, they asked me for a cert and could not believe I did not have any gue cert, but it was no problem to rent tanks. Also it was not a problem to find buddies.
ZG didn't even mention that I didn't have a GUE card. And IMO is one of the easiest going dive shops in RM.
At least in Florida the GUE "problems" is largely left to the prior generation. The modern GUE is largely easy going.