I don't know what 3rd party repos are, but I can't do anything about them and open programmes, as I can't get into Zorin at all and the mouse has no effect on these open apps - it did help me close some of the open apps, but not these. These, I think, are startup apps. But all I can do is turn off the computer using the Power button.
Reinstall Zorin 17 Pro from Ventoy, then try to run Time shift and Deja Dup - yes?