I have a feeling you're out of luck here. The door calls the "Collection", and the only params are A, B, ZZYZX, and the name of the panel object. The collection calls the custom panel itself, and the only params are A, B, and ZZYZX.
The trouble is, the add-on writes the collection macro based on what custom panels are available in the loaded libraries. I assume it does this from scratch every time the libraries load. You could in theory add code to the collection macro, but I expect it would get written over on reload.
I think you would have to save a copy of the door and write your own panel call into it.