Is a PoE switch suitable for use inside the cabinet?

Yes. PoE switches are routinely installed in data cabinets.

The part worth thinking about is heat. A PoE switch may be supplying power to cameras, access points or other devices while also doing its normal switching work, so a heavily loaded unit can present a rather different thermal problem from a lightly loaded non-PoE switch.

That doesn’t automatically mean you need a roof fan. It does mean you should consider the switch’s own airflow, the heat being produced by all the equipment and the temperature of the room around the cabinet.

A patch panel and an idle five-port switch are one proposition. A heavily loaded PoE switch feeding a small constellation of cameras and access points is quite another.