It really all sounds like "personality conflict" rather than bullying.
I have seen this in seeveral depts.
The people don't like each other. Whoever is in control is accused of "bullying."
Could be-- the bully's personality is in conflict with 90% of the faculty. If not more.
If this is as long-standing as you describe, then why didn't someone advise this new tenure-tracker 6 years ago? It sounds like your department needs a formal mentoring program for new faculty.
We do, and guess who was the mentor? The point of my story is this: the junor faculty member needed to not STFU. I think staying quiet allowed it to continue.
I was up for full at the time. So, I didn't get a say in the mentoring scheme.
I made full despite having a shouting match with the bully in the middle of the hallway one day over their behavior with me not long before the vote. Now everyone is co-mentored (at least on paper) so that if the bully gets in their the effect is mitigated-- or so goes the theory.