And, back to the OP:
I don't recall if the doctor's name was ever uttered during the podcast (as a Punk fan, I listened to the whole thing and even I thought some of it was just completely over-the-top and unnecessary bitching on Punk's part....with Cabana sorta enabling him throughout), which will make it hard to prove the case, if the name was ever said. If the doctor was named during the podcast, then both Punk and Cabana share responsibility, as Cabana had the opportunity to edit out that part of the podcast. If it had been a live podcast, Cabana's responsibility would be much lower since he can't control what a guest says. He would still have some as the person who provided the forum, but not so much.
As to the case itself, I'd be surprised if the case ever saw the inside of a courtroom, because it would be a lot safer for Punk to pay a half-a-million or three-quarters-of-a-million in settlement to make it go away than to take the risk of going to court and being ordered to pay the full amount, whatever it ends up being. It's also safer for the doctor, as $750,000 is probably a lot more than the doc makes in a year and he hasn't (so far as I'm aware) lost his job with WWE, which means he's still making his salary, and going to court is always a risk. All it takes is half the jury (in most civil cases) siding with Punk over the doctor, not an altogether unlikely thought considering how most Americans feel about doctors who work for "sports organizations"....or any corporation, for that matter, and the doctor gets nothing.
wk