Hey Pedro, what focus mode did you use for each respective shoot?

Do you use manual point selection, full auto, single shot with beep confirmation, or continuous focus tracking mode?

As for having deleted images, did you Shift Del(ie. obliterate) them , or just delete them the normal manner(ie. they could still be either in the recycle bin, or retrievable via a recovery program).

Not sure on your computer experience level, but when you delete something(even shift delete), it doesn't actually delete the file, it removes the listing of it's location in the internal catalogue of where files bits are stored.
So there could be a possibility that if you deleted (say) 200 images, that some may be still retrievable.

If you could post up just one of the missed focus images with full exif, the full exif data will reveal all sorts of handy camera settings you had used at the time.

I personally can't see how 45°C ambients would create such a variance in focus ability on a lens .. noting that thee are hotter parts of the world and cameras and lenses still operate with reliability.
As a slight aside, I've shot in roughly 45°C ambients, but not with any humidity tho, always very dry central Aus locations. Not that I've specifically searched for it, but never seen any focusing issues in those images due to ambient conditions.
I have missed shots, of course as you may sometimes experience, but not a wholesale ruining of a particular series, en mass.