I am not a 'freak' about Pokémon either, but since it was caught in a Cherish Ball that means it is from an event, and the OT should have been WISHMKR.
However, it would be nice if you could send the Mew back, in return for the Jirachi.
I was offline, sorry. I can't be online all the time just to answer your VMs.
And I'm getting angry because;
1. You said the Jirachi was legit, and now you are saying you don't know if it's hacked.
2. I know it's a game, but there's a chance I just threw away a 100% legit event Pokémon, in return for a hack.