The Doctor quickly concealed a frown, then wandered over on the pretext of gathering a few fish from the Beetles to reassemble Del a bit further.
Staring at a wall, he said offhandedly, "You saw the med ward the TARDIS has aboard - she'll fix you up better than any hospital here could." He scoffed and half-laughed. "Specially Cardiff hospitals.
Come on back, get that shoulder set and rested. You'll need it soon, I imagine."
With a quick glance at Booster, and as quickly away, he turned on his heel and headed off to roust the others.