"Registry object is not an object in" with "fetch_session_complete"

[cellarius]

I gather you did some standard debugging. As I said in another thread: If something does not work, start simple.

Have you tried setting your variable to something else than true, then printing the variable in the second plugin, to see if it is set?
Have you tried an echo statement in your if clause, to see if the code is being run at all?

Stuff like that.