You don't mention the capabilities of the clients. Newer WiFi standards handles multi-client streams better
Are you prepared to separate different clients onto different bands?
For that budget, you aren't going to get more than a consumer grade device, so temper your expectations.
Personally, I've avoided TP-link from years ago with their terrible firmware (to the point of being unethical) and no support. Not sure if they've gotten any better. Netgear was the better firmware (even then not good, and gotten worse) of the consumer router/access points, but if you need reliable, I'd avoid consumer gear outright
You are asking a lot of WiFi (doable with a professional setup, likely to be error prone otherwise). It would be much better to cable the stationary cameras
and be sure this wireless network is dedicated to the cameras, and traffic segmented from other networks
