Maybe I am naive. The thing is, if you look on adultwork or saafe, etc or other listing sites, you see a lot of places to rent for prostitution. You need a) deposit b) to be discrete and sometimes c) to adhere to no drugs or drink policy. The location seems to be one that would be listed for that kind of rental. I have looked on adultwork to use places for other purposes (nothing to do with punting), as they rent out to you for cash or deposit for an hour to a month at a time, no references etc. you can even rent specially made fetish flats/rooms etc with no references. They don't really care what you do there. I have rented a place (nice, actually) for half days so I could make an advert. Note they don't live there...they just work there. There is a cut off time when they can't work everyday (in all the listings I have seen). As adultwork, for example, is international, I don't see why they couldn't have done that themselves?
I don't mean this to be evidence that you are wrong, but I had assumed that this ,or along these lines, is what they had done.