If Gale is in a sulk, possibly still from the 43rd minute subbing, then he's doing himself, and the club no favours.
However, different people react differently & need different treatment. It's up to SS & coaches, and up to the senior players, and up to Gale to sort it out.
You don't just abandon him, you work on him. He's a decent player, only 23 & a lot to learn ... so help him learn it.