Well, I just tried an experiment tonight and the results were, unfortunately, what I figured would happen from my prior experiment (but didn't) - and, obviously, the massive difference in the temperature was the culprit.
Last time it was striploins that were on sale. This time it was bone-in rib steaks. 1 1/2" thick.
2 hours @ 130F to produce a beautiful medium-rare steak. Then into the ice bath for 30 minutes to stop the cook and cool them all the way through. Then I put them into the fridge for about an hour....then into a cooler for transport, then into my Grandfather's fridge for a couple of hours.
We got his propane grill blistering hot (buried needle, way past 700F - tried cooling it pre-cook so I could get a reading - no dice).
I did 4 minutes total - 1 minute per side, so each had 2 minutes total, alternating.
The steak, while still very tender and delicious, was well done (except close to the bone).
Further experiments required to get a similar sear to BBQ-only on a cooled sous-vide cooked steak.
(first experiment was my electric grill which tops out at about 465F, currently, replacing a part or two to see if we can't get that up to 550F).