Ah. The Avers versions (which don't seem to have many fans either) are library-produced talking books for the visually impaired rather than traditional retail audiobooks, which is why I hadn't heard of them. As such, they don't seem to be legally available to general readers, though I see they've shown up on torrent sites.
I don't mind Dotrice's voice when he's doing male characters close to his own age, but his attempts to do, say, Daenerys... oh my. I don't enjoy that style of audiobook at the best of times, and Dotrice is not the best at that.