My impression was that the Fetterman campaign intended to cancel that debate. That was before the firestorm created by the NBC sit-down. After that, they HAD to go through with the agreed debate.
Fetterman’s campaign was going thru the motions of debate preparation. 2 practice session run-thru’s were scheduled with the debate set — including the close-caption teleprompter system. Fetterman went to the first practice, blew off the second. Given his obvious handicap that is inexplicable unless he never intended to go through with the debate.