Co worker comes looking for you to make you aware of an important but low level urgent matter.

This person is told you are at lunch at least twice by another co worker. They also never bother to email or call your work phone the number of which is in your email signature.

The individual then tells your boss you were nowhere to be found (your boss always has your back but is retiring this summer)

You share one degree of separation with the CEO (their close friend) whom said turkey reports to (to my knowledge said turkey has no clue of this)

The offending party has a history and pattern of anti social and passive aggressive behavior and you've successfully leveraged this for increases due to a proven ability to work with difficult people.

You have a substantial collection of correspondence illustrating said behavior

How do you proceed given the aforementioned ?