Osmond did something the same on her combo and she didn't get a fall either.
That explains it. If Poutine cooking says Kaetlyn's is not a fall, then the judges on the men's side also have to do unagi cooking and say Shoma's is not a fall either.
Though the most likely explanation is that if a skater's weight is supported by two blades and a hand, the hand supports 33% of the body weight and that is not a majority.