Integrity teams at FB are teams that handle abuse on the platform, and other bad things (fake accounts, spam, malicious developers, malicious ads, ...). Why integrity? Bunch of teams (not all) that did abuse had integrity in their name (like site integrity, platform integrity), so I guess that the name just sticks.
And what does VP of integrity do? Manages organization that handles abuse on the platform.
Nah, I would think he's their friend as his role is likely to mostly involve promoting "company culture" in all-hands meetings and via the corporate blog.
It's facts that they all avoid or diligently rework to fit their version of the truth.
You know how banks have someone who's job title is something like "Head Of Fraud"? Who's role is to work out what a "reasonable" allowable amount of fraud is, small enough that it can be de-risked and budgeted for, but not so small it becomes "more expensive that it's worth" to fight it? An then to put processes in place to monitor fraud and ensure no more fraud occurs that planned for?
That's what _I'm_ imagining a "VP of Integrity" at Facebook does.
And what does VP of integrity do? Manages organization that handles abuse on the platform.