The auditor has a hugely inflated ego, something that might be a sign you're dealing with a narcissist. It's a pretty huge claim to make that you've "been in the industry longer" than anyone else, but that's the sort of thing you'd say when you're that kind of person.

Everything they said is surely made up, and if you challenge them on their facts, they'll attack you in return.

Yup. Sounds like a fairly classic case of workplace sociopathy -- the sociopath who gets promoted because they tell lies and bully the folks below them into obedience. (Not the kind of -- much rarer -- sociopath who is violent or robs banks, but still a royal pain in the ass to run across in a business context because any attempt you make to deal with them technically will result in manipulative social retaliation rather than "oh, my bad".)