We just started hitting this same error. Are you able to share the solution from ticket #20190963 in this thread?
Seems like it pops up here and there - I found two other threads with the issue but without any solutions posted:
https://community.shotgridsoftware.com/t/apps-not-available-in-the-ami/16717
https://community.shotgridsoftware.com/t/cannot-clone-configuration-seeking-solutions/14482
Anything help would be much appreciated!