Anybody recall the Mythbusters test?
https://www.youtube.com/watch?v=o8dhMF3IqbY
Makes me wonder, if people pay $40-60 for their FPS games would they pay a similar amount to play one round in person? Of course we'd need a much larger and more complete game, consisting of many "levels" like the ones posted (I realize this "level" was physically split).
If you look at how the Mythbusters did it, they took a fairly small space but directed people on a maze like path that greatly increased the "play time". A large facility like the one in the OP could probably be laid out to take an hour by the fastest players. I don't think you'd want it to take the usual 4-6 hours of a real game.
In both cases the "enemies" weren't really after them either...not sure if they need to be or how it would be handled if it were. I'm thinking normally just let people play all the way through. Perhaps have "difficulty" settings, in the hard/er mode/s allow players to get "taken out" and have restricted access exits to take players back to the start (you'd need special exits anyway, for emergencies). Pull players out when their time is up. Maybe mark the exits like save points, give them a card so they can come back and try again from approximately where they left.
Normal play the bad guys shuffle around and may try to surprise you, but they aren't running you down or really attacking. In medium difficulty, allow the enemies to move faster and perhaps have melee "weapons" to attack with. In hardcore, let the enemies have free range to run around within their area and allow some of them to have ranged weapons.
I know people pay good money to drive a go-cart around a static track...problem with an FPS is you need to pay the bad guys. Unless you could get people to volunteer to play the bad guys, and make sure they stick to the rules so as not to ruin the fun of the players.