So happy that he had a good experience la!
So? Any negative effect on Exam today?
I think you made the right choice to let him go for the match la!
Good chance for EQ and AQ practice!
Of cause it would not be recommended for "important" Exams, such as HKCEE or something.
But exam was NEVER a last minute thing anyway and multiple important events happen at the same time is a common fact of life, why not practice handling it early wor!
I once had a big fight with my GF right before a final exam but I still got an A. Not recommended for everyone but your son might face similar situation sooner or later and sooner is ALWAYS easier IMHO