Finally fixed my lid!
Here I’ve detached the black cable/strip, removed the lid, and carefully removed all the old glue.
I next removed the back/top strip INCLUDING the hinges and removed glue from the matching side. (And took no useful pictures.)
Then I cleaned with alcohol and used JB Weld Clear to join the parts. Since I removed the hinges it was easy to join the sides once glue was applied, still detached from the Glowforge.
After curing I reattached the hinges (and now attached lid).
So far so good!