Quite a tale.

My wife is my biggest supporter.

Cool.

In 2h I got a call from the waitress wanting to talk about what happened and why I fired her.

Hang about, hang about...

After this event at lunch, the waitress had finished her shift, did all her cleanup work, went home (right after your wife), went on the internet (right after your wife), read a “you got fired” message on facebook (right after your wife) then called you to ask about it... all in two hours?

was able to give an alibi as to when this message was sent.

Take a timeout from watching Dateline. This would only make sense if your wife and the waitress were twins with that special telepathy to do the same thing at roughly the same time without consultation, only 10x faster than normal humans. YTA for making me read this.