I am not convinced that deprivation of extra curricula activities is productive to stopping bed wetting, because it's not a conscious defiant behavior. Not truly a behavior at all.
And he's also, 3. I like pfrogs suggestion, i just suggested similar on another thread, in this forum.
Edit

n a personal note, couple of years ago I took my dad, to his first Bruins hockey game. Come to find out, his dad had pulled his opportunity to go, in his youth, because. ......he'd wet the bed...
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