He's not the one who should have had to apologize here, it should have been Aya and especially Ato. It would be one thing if her anger and distrust was pointed at Ato, but it wasn't.
I understand what Aya wants to do and is trying but all she's doing is going by how she feels about the situation and making it worse and/or blown far out of proportion because of it and because she refused to listen to the explanation when he caught up with them.
Overbearing bestfriend gonna be overbearing, I guess.