What kind of flood cleaning chemicals destroy glue and faux leather?

Back in March our house got flooded - luckily it only flash flooded under the doors and went under all the carpets as the water ran down the hill we live on, but it was enough to damage all the carpets and kitchen units as these have no carpet underneath them.

We were told by our housing association that we'd have to move out for three months and any items that were ok needed to be either taken with us or moved upstairs for safety.

We had a faux leather chair that went into storage, and I had some Sennheiser headphones with like a faux leather covering.  Shortly after we got back we started seeing black bits everywhere, all over the carpets, we realised that both the headphones and the chair were just falling to pieces.  The faux leather was just disintegrating - there was also a few other faux leather items that were all doing the same.

In addition to this, we also found that whatever is attacking the faux leather is also attacking anything with glue.  We've got Disney Christmas ornaments like the one with Nemo in a water jug and we've found that's come unglued, my DSLR camera (which I took with me) all the rubber handles have started to peel off, even the glue in the UPVC windows/doors has like melted and you can see it all sticky and streaky underneath the doors.

We asked the HA for a COSHH list to see what chemicals they used but they've refused to give us one. Does anyone know what type of chemicals they've used in the house that could cause this?