The Master's laser screwdriver does have a few 'repair' settings, believe it or not, but he doesn't suggest it. Even if it weren't under isomorphic control, he wouldn't let apes use it on each other. Instead he smiles down benignly at Daniel.

"Aren't you the busy bee," he croons. Then he glances at Howard.

"Howie--" Oh, he does love the reaction he gets from that. "It might be more trouble than it's worth to stop him from working. Surely we can find someone to look after him down here." Bringing Daniel above, in the state he's in, will surely attract more attention than he'd like.