Is there a /slight/ possibility that the Frosty Claw Vending Machine could give out a Glacier Potion? I have tons of tokens I want to spend and I'm saving for a Glacier Keeto :) Thanks!

Not specifically, but all vending machine do have the option (albeit very rare) to give out potions.

You'd mos tlikely have better luck with just trying the Polar Ice Fields as often as you can; I've gotten 4-5 Glacier Potions that way.