I think Fleetwood Mac may play one Finn related song (and I'm sure they will pick an obscure one....possibly even a Split Enz one....Six Months might fit). Come to think of it. One obscure Crowded House one and one Split Enz one would be great. Just don't play Don't Dream anymore! I like it but there are others that would fit better. (and Neil must be sick of it for the time being....)
The thing that bugs me a bit about this is the fact that there is a past of band bickering....and Stevie Nicks comes across pretty bad (and self centered)....so for that fact alone, surprised Neil would want to surround himself with that. And also being a replacement after a sorta bad split. Surprised he would join for this reason too. That's why, I think it would be better to create his own supergroup (with the Petty guitarist, etc) and create new music with them.