No they weren't. The people of Sodom wanted to rape Lot's guests. Violent criminality has no place in any libertarian philosophy I've ever heard.
Think about how silly that post is.
The members of that mob would have been some of the regular people of the town, the libertarians and leftists who’s inner beliefs and tolerance, and anti-social conservatism shaped the town, they weren’t at the house espousing political philosophy.
Even libertarians can be violent, ask the typical pusher, or pimp, or porn producer, or abortionist, if they ever get drunk and rowdy.