I'd give the mod team the benefit of the doubt that the offense they've all resigned over is not so mild that it could be committed unintentionally.
I don't think that's necessarily a safe assumption, particularly in today's cultural and political environment.
I don't know whether that fits in this case. I'm inclined to think not; I suspect that those who freak out over trivialities, try to get others fired, find out that they can't, and then resign, tend to have a public hissy fit when they resign. I'm not sure that what the Rust Moderation Team did counts; they seem to be trying to not air dirty laundry (or what they perceive to be dirty).
Odd code of honour there. They've made a lot of dramatic insinuations about other Rust contributors, basically asserted that they're all bad people, and provided no detail. That's the opposite of integrity.
That said, there is still a bit of a game left to be played. The mod team just played their trump card, by instantly making the matter super public. But by keeping the specifics close to the chest they both keep their integrity and they give the next mod team some leverage for their interaction with the core team to resolve this situation.
It's really good btw that they're keeping the specifics private. Having someone publicly lynched is never a good situation, it's probably something that's offensive to a group of people, but the person(s) who caused offence probably have no bad intentions. It's hard running an organisation with a diverse group of people. You'll never get everyone to settle on the same moral values so it's inevitable that you'll get someone who is unapologetic about some value they hold.