The main answer I wanted to give is one that would ruffle some feathers and I didn't want to start something there. Instead, I'll start it here

The best chance of ever hearing any new material - be it live shows, studio outtakes (either Ozzy or Quiet Riot), video footage, etc. - is to petition Delores Rhoads with a formal petition from the fans with a thousand or more signatures.
For those interested, the entire interview with Kevin is here - I don't want anyone to think badly of Kevin when I take only part of an interview to present here. If you want to think badly of him, read the whole thing and post in a different thread, please.Kevin DuBrow wrote:
...he was brilliant, he was gifted, he was hilarious and a wonderful person.....he was not an angel, the way he is made out to be.....I don't think anyone is. I think it's a shame his memory is not being cultivated the way it should be, like the way.......there's certain bad things about the Jimi Hendrix estate, but at least the memory is being cultivated.
FIB MUSIC: What do you mean by that?
Kevin: Music still comes out from the Hendrix estate. There's no music that comes out, because Randy's mom has such a tight reign on things...there's no merchandise, no nothing comes out of the Randy Rhoads estate, it just sits there.
FIB MUSIC: I was wondering why there hasn't been a release of Quiet Riot I and II on cd.
Kevin: Well, I'm not trying to put any effort into releasing them, but I think they should come out, but I don't want to hassle with it.
FIB MUSIC: Does Randy's mom own the rights to those recordings?
Kevin: I could put them out if I really wanted to, because I was a participant on those.....I wasn't a hired guy and the other three are still alive, me, the bass player and the drummer, so it's a vote, the other three out-vote the non surviving member, which is his estate. Having said that, do I want to hassle with it? NO. I don't. There are other things in life to do.
So I believe that the main reason that none of the stuff we are hoping for is released is because Delores says no and those involved are respecting her wishes.
Now I realize that a number of members of this site are friends with the Rhoads family, so if I am way off base here, please explain. I am basing this belief on the comments above by Kevin and on comments Kelly Garni made when I sat and talked with him at his Nevada studio.
It is my understanding that Delores was against an official release of the Quiet Riot DVDs that are now circulating because she didn't think they were of professional enough quality to release. We fans are thrilled with such gems, regardless of their quality. Sure I'd love crystal clear video and 5.1 surround sound audio, but I was ecstatic just to see Randy run around the stage!
At any rate, those are my feelings on the subject and I'd love to hear feedback from everyone on this subject. I have idea regarding starting such a petition, if anyone is interested.