I have had this problem many times before....with many different types of pitless adapters/units. I have welded pipe taps onto their corresponding couplings and keep them on the truck...I have a 1" tap welded in a 1" coupling, 1.25", and 2"...... So, when this happens, I screw the tap on the pull pipe, run it down and clean the threads out with the tap, and then screw in the pull pipe. I've even pulled with the tap before. You can also get a taper tap fishing tool and pull with that, but it will probably ruin the threads on the spool.
It's important with a spool pitless to pull straight, so I doubt you'd have very good luck pulling with something in the wire slots.