True, for the interogation room that's absolutely correct.
The other angle, though, is that there is also a certian amount of intimidation that is simply carrying yourself in a manner which would make people reluctant to test you, or get in your way, regardless whether or not you are waving a gun around. Among High Rollers, this should function even to the point where even big monsters might rather sit and talk over risking a straight out fight with someone like that. For example, a character with high Charisma, Intimidation: 5, and Intimidation Mastery, should be able to step into a room and make all the mooks and even their boss think twice about going for their guns… (or perhaps make them go for them that much faster.)
Unfortunatly, there isn't a good system for describing this…
The real issue I'd like to address, is the "The Vampire/Werewolf/Cultist just isn't scared of you…" situation. Simply because there comes a time when any Highroller worthy of the name is capable of eating those monsters for breakfast. And there should come a time when those monsters should pause to consider whether or not they actually want to die at this roller's hands, or if they wouldn't rather cut a deal.
The best part, is that the Charisma, Intimidation 5 character might not BE capable of eating said monster for breakfast, but should still be capable of making them think twice about attacking him.