Santa has cancer.
He flew down to the Cleveland Clinic for treatment.
Left the elves in charge of things.
They know what to do. They’ve been through this before.
The old man gets chemo and radiation, loses all his hair and eyebrows and beard, forty or fifty pounds.
Glue on the fake beard and put on the wig.
Cover the burns with makeup, make sure the catheter bag is taped to his leg securely.
Everything sorted and labeled, RFID tags and GPS coordinates.
The sleigh practically flies itself.
Good to go, say the elves, and it’s off into the night.