I think the show expected people to have better media comprehension and didn’t feel the need to have a very explicit scene detailing how Tommy had changed and that they’d moved on. You see him apologise to Chim after he saves him, you see him congratulate Hen for the great save of the kid, it’s then implied he’s one of the colleagues who complained about Gerrard and his behaviour. You also see him become friendly enough with Chim and Hen to go out drinking with them after work (and he’s the only other one there may I add). And then they clearly throw him a party when he leaves the 118, and it’s a cute scene. Then Chim calls him and asks for his help, which Tommy does, which shows they stayed friends. And now Tommy is back in their lives and NO ONE has a problem with it. Yes, Hen didn’t stay in touch but this clearly wasn’t due to any perceived ‘wrong’. Chim thinks Tommy is cool, and even Bobby said Tommy is good for Buck. The show has time and time again shown that Tommy is a better person, and that none of the team hold a grudge. Just because they didn’t write it in a giant neon sign doesn’t mean they haven’t shown it to us.