They couldn’t even spell the name of the base correctly, never mind getting the Service right.
Quite often if the compulsory drugs testing team go to a training base they will test all the trainees, but usual protocol elsewhere is that they have a (somewhat but not entirely random) list, and if your name is on it then you don’t leave camp until you’ve been tested. If you’re not on the list it’s fine, do what you like. I have had to get one of my team off camp despite being on the list as our unit didn’t have a medical centre and they had an appointment at a different camp to see the doctor about half an hour after the team turned up. We went and had a very quick chat with them, they were reasonable about it and actually took them off the list on that occasion.
I’m not a supporter, but this is half a story with limited context. If H was on the list but allowed to leave camp without being tested, someone higher-ranked than him definitely intervened to make it happen, and he’d have been tested another time they turned up yo a base he was at.