Global Inbox not working anymore

i am not sure what is in that folder. My mac not at hand to look. but I suspect root of issue.

See Moving DEVONthink 3 to a new computer - fresh install of everything - #4 by ccornell29 for instructions how to move to a new computer. post by @BLUEFROG summarises. compare with what you did.

I think if i were in your current situation i would uninstall DEVOnthink and then reinstall. simpler than piecemeal repairs. then copy the databases (if not already there, preferably in a sub folder of your user folder and not under ~/Library.).