(stable) Fix inverted check in audit triggers for "uninvolved owner"

Summary: See D20126. I was trying to be a little too cute here with the names and ended up confusing myself, then just tested the method behavior. :/

Test Plan: Persudaded by arguments in D20126.

Reviewers: amckinley

Reviewed By: amckinley

Differential Revision: https://secure.phabricator.com/D20135