Voting yes on frostbite as well.
I had a broody girl who wouldn't roost with the others and slept alone in a nesting box which is sort of dormer-style ( bumped out from the main coop). She had a touch of it on a few spikes just like yours. I'm surprised it's almost healed.
We wound up covering the outside of that part of the coop with two big moving blankets for extra insulation.
Coat comb and wattles with a good layer.
Things you can use:
Vaseline
Chapstick
Aquaphor ointment
Bag balm
Carmex (in the little jar)
Probably more, just can't think of any right now.