I disagree, bureaucracy is the way to go here:
Firstly, make a check of your NI contributions - it sounds like the kind of dodgy outfit that deducts them from your pay without paying them into the fund. If they haven't been paid you can have great fun as they get investigated.
How about some allegations about fire safety, etc - surely you know about some skeletons in the cupboard?
The best one of all is allegations of VAT fraud.