Well, the selection seems to split largely into three groups:
People working on the new series (Roberts, Gatiss, Russell)
People on staff (or used to be on staff) at BBC Books (Cole, Richards, Rayner) - possibly that made it easier to get their OK for a reissue.
Original series legends (Dicks, Aaronovitch).
You do wonder whether some of the 'definitive' 7th/8th Doctor authors from the 1990s and early 2000s are spitting blood that their 'masterpieces' have been overlooked...
Having said that, there were some author-driven short-run reprints of various BBC titles by Lance Parkin, Kate Orman and others last year (still some copies in my local Waterstones). Perhaps the fact that they're in print ruled out any notion of reprinting them?