Downtime is a tricky one, as being one of the original financers, Ian Levine belives he has the rights to further releases. But he wouldn't do it without the Doctor in it.
The PROBE stuff is out, but its on DVD-R, so unlikely its region locked.
Big Finish showed it's possible for a third party to get the OK to use the Doctor, so maybe Levine (who, lest we forget, was a consultant on the original series and even composed the theme to K-9 and Co. so he's not unknown to the BBC) can get the proper rights sorted out. Only thing is I remember reading the novelisation for Downtime and I don't remember the Doctor being involved (by comparison, when he novelised Shakedown: Return of the Sontarans, Terrance Dicks devised a framing storyline with the Doctor). The last McCoy story comes out on DVD in a few months, so it's possible 2 Entertain (or whatever they call themselves now) might be interested in something featuring him so they have something new to offer during the anniversary year alongside the inevitable reissues.
Shame to hear PROBE is only on DVD-R. They play OK, but I've never been impressed with the picture or sound quality of those types of releases (one reason why I've been reluctant to spend the rather high prices Warner Archive charges for its DVD-R releases of things like Girl from UNCLE). I don't expect to see Downtime on Blu-ray or anything (IIRC it was shot on video like most if not all of the independent spin-offs) but I'm still hoping to see a proper DVD release down the line. That said, DVD-Rs do tend to be region-free so that's good to know.