@TPLinTX,

If the cameras are able to operate intermittently, I would suspect that it is a combined SSID (2.4+5GHz) and not just a 5Ghz connection. If it was only made up of only the 5 GHz band, a large majority of devices would have problems, and it would also require the assisted living facility to place an Access Point in each room.

Most settings that you could change to force the use of 2.4Ghz for the cameras will unfortunately be on the router managed by the facility.

Most Range Extenders wil allow you to take a wireless signal, and rebroadcast the signal in the way that you need - however a login screen from the facility may cause difficulties during setup.

Does your mom's room have any hookups for an ethernet connection? If so, you may be able to connect a regular Access Point to the network. This would give you control over the devices that are broadcast by the AP, such as disabling the 5Ghz connection, while also allowing you a few wired connections for your TV or laptop.

Depending on the size of the facility, you may consider getting in touch with their IT administrator, as he may be able to provide a few quick suggestions or help you with the problems.