If they gave consent then isnt it okay? The person who said its okay for them to get pushed in will likely have known the consequences of getting pushed in like wet clothes or might bump their head. So in the end it might just be a stupid gag saying they want to be pushed in, But not a reason to say its not okay. I would say its okay if its consensual pool pushing
I have to say I haven't met anybody that would be willing to get pushed in a pool. I suppose if your a goofy person and your like push me into the pool or else I'll push myself in, Then I guess you gotta go somewhere but I really don't think that is very nice so I wouldn't do it.