How is the audio on those episodes? I read that many lost episodes cannot be animated because the audio quality isn't as good.
The late Graham Strong started his 'crystal clear' recording around DMP 8, so from there through The Wheel in Space the audio quality's just fine. The ones before that came from David Holman (used in the Loose Cannon stuff and a couple BBC CD releases), and some Australian recordings brought us the animated Invasion and cover The Space Pirates. It's all listenable, I don't see why they should have any trouble using it.