Much good advice already given…
Are you seeking to make an insurance claim or similar? Wondered if that was why you were looking for an expert opinion.
Presumably the sudden rise in temperature from 11 to 18c was just the air temperature adjusting to the ambient temperature. Even a rise to low to mid twenties on a more gradual basis would seem unlikely in itself to spoil wines. If these were older whites they may well just have aged a bit faster than expected due to the temperature rise, and as you note you had one spoilt bottle before.
Prior to getting my Climadiff cabinet, I had quite a bit of wine stored in cases in my garage. Mainly stuff intended for drinking over the next 1-2 years, but odd bottles of older wine remained for a number of years. The temperature range was probably quite marked over the year as a whole, maybe 0-22c, but the changes would have been pretty gradual in most cases on a day to day basis. I suspect I had a couple of bottles age prematurely, but certainly not all…have recently opened two Bordeaux reds from the 80s which were in pretty good nick. One white burgundy was pretty oxidative but it was over 15 years old! No real sign of cork seep or undue evaporation in any of them though.