For the Skull Helmet in multiplayer it says you need to have all other previous helmets unlocked before purchasing it for 1Cr. Does this also count the Recon helmet or no?

I don't think downloadable armour would be included, though I could be wrong.  Also I guarantee everyone will be using that helmet once they get it.

No it won't include Recon, it doesn't even include the armour from Waypoint either, just everything you can buy normally in-game with cR.