Its not beyond the realms of possibility that your deposit has gone missing. I have twice had cheques deposited at the counter lost by the branch in question (both times Nat West, different branches). The first ones turned up a few weeks later - they claim they were unable to process them until someone pointed out that they were missing - I thought this a little odd since they clearly have the name of the customer on the top line which should be a hint. They did however eventually credit them and also credit the missing 3p interest or whatever nominal amount it was.
Then, lo and behold, the same thing happened a month later, only this time they never showed up. When I put in a complaint I was gobsmacked to hear that they had no intention to reimburse me and told me to ask the cheque issuers to re-issue a new cheque. I pointed out I had no record of the cheques, and that I also had a nat west receipt for the deposit, but still they didnt budge. I have subsequently had to ask my solicitors to write, but have heard nothing back yet.
It seems the only point they are making is that there is a "chance" that the cheques might not be honoured, so they are not hard cash, but at the end of the day, that does not give them the right to write them off at zero.
Has anyone got any smart ideas as to how to approach it from here?