Ailerons neutral, right rudder and up elevator - exactly how you enter a snap roll or spin.
Adam Wojda at Sleap taught his students, including me, to enter a deliberate spin in this way, starting just before the stall horn would go off, holding the controls in that position until the spin had fully developed, and then starting recovery. I always understood that the manoeuvre, which was quite violent, was the same as the first bit of a flick/snap roll.
I'm with Con-Pilot on the possible cause.
When young and foolish, I tried it one day (at 8,000 ft) with a 140HP Cherokee to see if it could be spun that way if no other, and very nearly died of fright in the resulting almost vertical, spiral dive at Vmax + God knows what, and pull-out. It says a lot for the Piper build quality that the aircraft stayed in one piece.