I forgot to write, I do not think you should change your mind. If there is any way you can leave him so he misses out. I think it will send a huge message that you are not kidding and you stick to what you say.
Make him write out a promise that this behavior will not happen again. Have him sign it. If he refuses to write it, that is his choice and he will miss out. If he reverts back to the behavior you need to have a plan that has been explained about what the consequences will be.. Make them pretty tough..
Also you need to make sure you have a real upfront conversation with him about how misbehaving in the way that has been reported to you is very selfish. He is affecting other peoples enjoyment. He needs to quit reacting and start acting his age. Nobody likes a goofball. It is irritating and he is openly making himself look out of control.
I know this sounds tough, but some kids have just never been told, this is not all about them, They need to start thinking about others around them and how their behaviors affect others.
He may need to be taught how to control his behaviors. Have him count in his head to 5 before he spouts something in response to others. He may need to go and sit alone, to calm down when he gets over excited..
Teach him to read others expressions and body language. .. If he sees their eyes widen or they lick their lips, he is making them respond, in a negative way.
If they roll their eyes, their shoulders slightly slump or they take a big breath when he walks up, he is not really welcome and he may want to excuse himself for a moment and make a different approach..
I am sending you strength.