[wrxtasy]

Throw a few disabilities into the mix, top it with some age and voila...it's a project

You should have mentioned this earlier as now the only Kodi device I recommend is the nVIDIA Shield.
Why, because it runs Android TV OS and Android Apps that do not require the use of a complicated, confusing Air Mouse. These Air Mice are a PITA for use on a big screen TV, especially in your use case. The Shield is Plug n Play.

Control is by use a D-Pad, consisting of left, right, up, down and enter. It could not be any easier. Definitely steer clear of regular Android Lollipop only systems like the Q10 Pro.

The other point I will make is LibreELEC Kodi runs better than Android Kodi. There are far less complications in an Appliance like LibreELEC Kodi box that using regular Android Lollipop devices. No Air Mice again need to be used with LibreELEC.

Basing you choices on devices with only RCA connectors is going to lead you into trouble with Air Mice and sub optimal boxes.