That's a good idea
Simeon, youre a good eg, but sometimes stuff like this makes me wonder if you are maybe a little under represented in your team of experts.
You have provided countless referrals for leagl help to members of this forum, but it seems your own legal representative may not have offered you some advise to which, on the face of it, seems pretty low cost/low risk and very sensible as a course of action. The bank may even then provide you the necessary information on how to make the claim. Presuming the funds were in fact coming from a loan and not the client's reserves of cash.
Arent there also avenues with the council you can take to have the council remove them from teh property given no OC has been issued?
How did the client get keys to the property without settling?