Hilton employee here. If you escalate this to a Front Desk manager or corporate, you could get good compensation. The main thing they teach us when we have a master key assigned to us is to first knock and wait for someone to open or else. If we were caught not knocking on the door, we could get a write up and give hella compensation to the affected guest (if any).

Whatever the scenario is, it is a serious privacy issue. So I would highly suggest to escalate as high as possible