The Braddock who hung tough with Joe Louis, even put Louis down, could beat Galento. Otherwise, Galento grinds Braddock down in a typical Galento foul-filled bout.
Braddock would nullify him with his distance control, reflexes, spoiler momentum/pacing, and his jab.
Both at their best, I think that a Braddock decision is the most likely outcome. Throw them together otherwise, and you are more likely to draw a good version of Galento.
Galento would always be dangerous, and would have his moments, but Braddock's toughness, gameness, and all-around skills carry the day. Braddock UD.