Get a 'zapper' the things that give of blue light you see in the chip shop etc, just put it in the room and close the door.
They will drop like flies!!!!!!!!!!! sorry.
I think you can hire them from HSS etc. If not get onto the local pest control man they do it all the time for wasps bees etc etc, its not that unusual actually.
I had to tidy up after a suicide years ago, bloke had dropped himself out of the trap door on a rope, lovely. Fluid had soaked through the chip board etc. Landlord said save the boards, Loss Adjuster said they HAD to be removed and replaced. So thats what we did.
You cant get round that sort of thing these days. Its common sense really, if the owner of the property doesnt agree give him a letter saying in your professional opinion the floor should be replaced etc, if he doesnt well thats up to him. I would rather sleep at night than worry about it coming back to haunt you. !!!!!!!!!! (Who writes this)
Murky