Multiple available RAP is fine and generally suggested.
As for 1 RAP and then 9 to 10 Mesh, well.. it may work, just poorly. They are all going to have to contend for the same airspace on the same network to maintain that connection. If that space is busy, or constantly in use, it may be a poor choice. If all the cameras are timed to burst information during intervals, or something that can be time delayed, you may see less of a problem if they can also be deployed to take advantage or something like that.
The heartbeat losses.. you may need to wireshark that, but in the past, those types of issues have been tied to a firmware version more than anything else I have seen.