I agree with your policy but you should do something about it. If Im the in charge I would do the next thing just to lower the ninja looting and inform the players:
- Update the rules
- Put the news about it on the website home page
- Put the auto news line in game like promoting streaming. 12K people will read about it at least few times during the day.
Btw, I always take scr shots about my rolls just in case cuz in the past people used photoshop and they get ban themselves for reporting fake reports.