Yes, I think that's a correct sentence, grammatically. Whether or not it's saying what you think it's saying is another question, though. This is how understand it: Something happened in the past ( let's call it outcome A), but that wasn't what you wanted to happen. Now, in the present, you're discussing the situation with someone. The other person mentions a hypothetical situation (let's call it outcome B) : something which could have happened but didn't. For you, outcome B would have been a preferable outcome, so you say "That's what I wish had happened". In other words, you wish that outcome B had happened instead of outcome A. I hope that makes sense!

Wow... looking at the sentence makes it even harder to analyze. I think it should be like this: That's what I would've wished to happen. If I'm correct, this sentence wants to imply that the wish didn't happened at a certain period in the past but wanted it to? If so, then I think the word "wish" should be changed to its present perfect form then just replace the word "happened" to an infinitive. Hope this helps~! Edit: I think you can also say "That's what I wish to have happened" too.

Eai amigo BR. Se for tipo "É o que eu queria que tivesse acontecido" então tá certíssimo.