Finding out whether or not a hotel's camera records

On September 20th, 2011, I accidentally left some cash on a lobby counter in a hotel. The money was in a small envelope that I had gotten from the bank. I was checking in that day, and I immediately recognized my mistake once I got back to my room. I quickly ran back to the counter to find that the envelope was gone. I asked the receptionist at the counter if I had left a small envelope, and they said "no". I now have substantial reason to believe that they are lying.

The lobby has a surveillance camera. I tried to get the surveillance footage of that day directly from the hotel, but they obviously don't want me to have it. At first they told me that the tapes are kept at a different location. They then told me that the lobby camera doesn't record, it only monitors. I believe they don't want me to see that they are the ones that took my money.

So here's my question. Is there any way that I can find out whether or not that camera actually records without the hotel knowing about it? If I could prove that the camera does record, and that the hotel is lying, I could have enough evidence to take them to small claims court.

I initially tried contacting the local police, but they were no help. They didn't seem to want to get involved. They sent out an officer who made me explain everything to the hotel before asking for the footage. I believe that if the police had asked for the footage without me being present, and if they didn't tell the hotel what it was for, they may have gotten the footage. But the police didn't want to do it that way. As a result, the hotel began giving these different stories about the whereabouts of the footage, and whether or not it even exists. Now they're on alert. Is there any way that I can find out whether or not their lobby camera actually records without them knowing about it?

I contacted a detective's office to see if this is something they could do, but they want to charge me boat-loads of money to do it. So I get the feeling that this can be found out. Is there any way to do it without spending lots of money? Thanks for your time, and for any help that you may be willing to offer.