Hmmm. I've always been able to get around that in my head for some reason. But, I can understand your reasoning. I always wondered what happened to the guy, though. He was the first recurring Time Lord nemesis for The Doctor, wasn't he? He appeared twice, right?
And it's unlikely we'll see him; The Monk is a character that's off-limits right now. I know of two Short Trips
stories that either didn't happen or were drastically altered because Dennis Spooner's estate refused permission for the character's use.