Many years ago I worked at a non-profit that was not family owned. However, the Executive Director let her "favorites" get away with unprofessional behavior. After 5 years, I left. The E D eventually lost her job due to a variety of management issues. The board of directors let the E D's behavior go for a long time until they could no longer ignore it. Unfortunately, in the meantime, many excellent employees left due to frustration and favoritism.

If H R is not an effective department, it is a huge red flag. I'd dust off your resume and start looking around. Plus, the vandalism would have probably pushed me to just quit. But I encourage you to find another job while still employed. Good luck!