When people leave by "mutual consent" you can't really believe much of the official press releases. If the two parties are still on decent terms, they will agree exactly what will be said regarding how great each other is.
If the the two parties fell out, then there is usually a legal agreement to say they can't bad mouth each other, so you get the "no comment" treatment.
There is also often a contractual clause that attached to the severance pay that requires certain behaviour.