I think we should go for the EVA-tied Distress Beacon route for a couple reasons:
1) ICly, an EVA-bound beacon would be able to transmit it's signal much better than one all snug up inside, the signals would be able to spread slightly faster and much more broader in whatever semi-encrypted frequency it's using. This could be used to explain why Pirates would get it instead of ERT, maybe the signal just bounced to them while ERT was busy and before TCFL could launch
2) It makes sense as a company decision. Think about it, NT has ensured there is no way a crew member can be without internals with all the Emergency Lockers scattered about. Hell, there are so many lockers, we often forget about them and how easy it is to hide in one when being chased. But yeah, if NT has the beacon tied to the roof or some EVA position, it allows it to be used in a better emergency. Command isn't onstation 24/7 and sometimes only 1 is brought to the station, if that person is killed from a surprise Lii'dra attack or from the rare terrorist, the crew is FUCKED unless they get the spare....which was probably stolen. Having someone, a vaurca, or literally anyone (since everyone has access to 6-minute lasting EVA gear) be able to go full Die Hard and scale the station to get and activate the beacon allows for emergencies to be handled. It also enables ALL of the crew to call for help, not just 5 people who will be prime targets by external threats
3) Imagine being an antagonist and joining a party of people going EVA to activate the beacon with the thing being that you plan on backstabbing them. Maybe you push one off when they're separated, now they're going to crudely die, echoing your name into the void as the others are now cautious. You pick off another with a makeshift weapon you have and when they're about to activate the beacon, you whack them off. Now the beacon hasn't been activated and anyone else who comes out will have to deal with you. It'll give chills.