Don't believe me? Check the http://pc.brinkthegame.com/. The Resistance has 4 wins on that map already.
No, the DLC is not available yet. No, the PC players don't have that map yet (and if they do, the numbers would've been a lot higher) (and if they do, then Splash Damage would've told us all about it).
the only thing i can think of is test runs my the devs
Probably because majority of Resistance outnumber security users and or just fight against bots. No wonder people are complaining about NO ONE playing it's because there is no lobby system for them to actually have Legita stats and show that Security aren't as bad as everyone declares them to be.