I doubt the cameras were ever recording (or attached to a recording device) - he was using them for surveillance.
There are reports that the swat team "exchanged gun fire" with Paddock before breaching the door with explosives and finding him dead on the floor from, what was described as, a self inflicted gun shot wound to the head.
This video contradicts that statement. The SWAT team didn't even know if Paddock was still in the room when they blew the door open.