Hi Tom
I have just read this and I am disgusted. There was a crowd of 5/6 renters at the lower pool beside Block 9 last week who were quite rough, drinking with glasses at the pool side, drinking and shouting on the terraces late into the night etc so I will check where they were renting as the area round your pool is very quiet at the moment and I might be wrong but it could have been them and the towels may have been left in the rental property they were in.
I will try to find out who rented the property for you and we will take it from there. My towels are always on the terrace with no problems and there are a number of Spanish owners here most of the time and their towels are on the chairs on the terraces as well so it seems strange that yours disappeared. Hopefully they will turn up and I will keep you posted.
Moira