Jeff appears to be wrenching on the nut holding the eccentric crank on the crankpin as the first step in pulling the rod off. Either the rod broke or the wrist pin broke or fell out.
Loose wedges were a problem when I rode back in1982. The crew used the pilot beam as an anvil to cut shims for the cross head/piston rod wedge as part of one breakdown repair. Another time they repaired a broken driver spring with a wooden wedge that they inserted. The G&Q was running on fumes for years.
Michael Allen