well, another update, and this time not good. I found the source of the damp...
https://www.youtube.com/watch?v=hgN7ZTAyXwQ
there's no way the dealer wasn't aware of this. I think the strategic mats show that. Have to say I feel duped and stupid for not checking this before buying.
I have no idea where to start with this. Is it worth asking the dealer to fix it or should we just go for a refund and find another one?