So, is the retrial on the issue of liability also or just on the issue of damages?
Ventura made two claims-- one for libel, and one for "unjust enrichment" (on the theory that Kyle profited by writing a book about Ventura). The jury awarded half a million for libel and another million and a half for unjust enrichment.
The Court of Appeals threw out the entire unjust enrichment claim, because an author doesn't owe money to someone just because the author mentions them in a book. That claim cannot be re-tried.
The Court of Appeals also threw out the libel verdict, because Ventura's lawyer improperly argued to the jury that they shouldn't worry about awarding damages against Kyle because any damages award would be covered by insurance. (That's improper argument in any case, and especially here, where there wasn't even any evidence that Kyle had insurance.) The libel claim was sent back for a new trial.