Have read that’s the case with NDBR, etc too. I imagine the police issue is probably one of logistical convenience for match days, given how the border between the two countries has developed and where this ground sits in relation to that. Seems an odd place to have built a relatively new ground in the first place, so close to different administrative borders but I can’t say I’m well acquainted with that part of the world.
I get the feeling with TNS it’s probably an agreement with / through the FAW to follow WG rules.