Wilfredo Gomez? If so then certainly Gomez by KO. Pac was not yet fully developed as a fighter when he was at the weight, and he'd be going up against a 122lbs Godzilla. Gomez was just too much of everything for Pacquiao at 122.
Most regard Gomez as the best ever at 122 & Pac was very ragged at that weight & got better as he moved up the weights. Gomez by TKO
Not EM at 122, nobody KOs Morales at this weight. Gomez would do well to actually win the fight never mind get the KO/TKO.
No one ever went the distance with Gomez at 122, and over 15 rounds the likely outcome in a match between the two best ever at the weight (Gomez vs Morales) would be either the referee or EM's corner stopping it late.