Sure, if you're playing strictly by the rules, getting captured on Turn 12 would end the adventure in failure. But I think it would be a lot more interesting narratively if you were to treat the adventure as a two-parter. Part 1 ends with the Doctor in prison. Part 2 opens with him making a daring escape, figuring out what the villains are up to, and stopping their plans in a dramatic fashion.
Just sayin'. It might be pretty fun.
This is a storytelling game so I'm all for that which makes an exciting episode.
Perhaps at the end of Turn 12 take a -1DM to make it 'interesting' and time is running out...