Mint works well on my Thinkpads

Debian

It may be possible to create a UI using a monitoring program like Zabbix.

You could create a custom dashboard that displays all the stats that they need to see.

This of course would be for viewing only, not controlling the schedules, retention etc

Markor on Android and Obsidian on Desktop.

All synced with syncthing

Look at Mikrotik. Very affordable and extremely powerful. Only do this though if you know what you are doing with networking

All my devices use Syncthing via Tailscale to get my data to my server.

From there, my server backs up nightly to rsync.net via BorgBackup.

I then have Zabbix monitoring my backups to make sure a daily is always uploaded.

Brother works incredibly well. Plug and play

Linux Mint is what I use and have no issues with my 3070.

Chimera OS might be something you can look into however I have not used it

Pop OS is also great for nvidia support