Scott,
The yellow wire is actually another extension cord... (I find these yellow flat cords attached to garage door openers constantly!) I'm starting to think they were sold with the openers!
The white wire coming from the FPE is attached to the neutral bus, goes out of the panel & swings in the breeze! Which BTW, the subpanel is doing as well... It's being held by a couple conduits, about 2 inches off the wall!
-Randy