Memory worms should come with instructions. They probably do, but people keep forgetting. Strax knows better than to handle the worm without gauntlets, or he did, before he touched it with bare hands. Maybe the Doctor shouldn’t have sent him, because now the worm is on the loose somewhere in, or possibly under, the carriage.
Strax is looking for it.
Unfortunately he’s still not wearing the gauntlets, so when he finds it he immediately forgets what he was doing. How did one simple little task get so complicated?
Well, if you want something doing right, do it yourself.