Maybe GP's mention of "boiling salt" does not refer to "table salt" but salt in the more general chemical sense. Perhaps they use Ethylammonium nitrate with a boiling point of 240 C (464 F).

Can you find that at a grocery store?

I usually order it here: https://store.p212121.com/ethylammonium-nitrate/

$111 for 25g. It might be cheaper to buy a new pan.

Boiling water with salt in it works well, and seems likely to be what OP means. Even boiling water works great.

I suspect a degree of sarcasm just wooshed over me.

It wasn’t sarcasm, per se, it was just a joke.

he's obviously talking about boiling salt water.