Attached is both a screen shot and a model with closed corner problem I am unable to solve.

Yes there is a work around of merging another tab/sketch to the flat pattern after the fact. But that does not show the results in the bent model.

I am trying to figure out if there is any way to set this up so that the bent part and flat part have a one to one relation.Without the need to edit the flat pattern at the tail end where that edit does not show up in the bent model.

And NO, I do not want to change the desired notch. The desired notch is the nominal desired welding gap to seal up the tank.