Although this is concerning, firestar has done nothing wrong to be fair.

If they were in constant proximity to you (killing your or not) and you had documented this over time (ideally in a short space so it could be classed as harassment) then the staff would take action.

Unfortunately, firestar just seems to be coincidentally going off map whenever you go back to your home or somewhere which has pvp enabled.

^that is all that is occurring and what you’ve so far described. There is no reason to confront firestar at this time.