I think they took the Silvermoon step out of the Outlands horde questline but not the Exodar out of the alliance.
I got the flag return part of Hard Knocks right after I entered WSG. O.O A single draenei had picked it up, I killed her (as a 80 shadow priest with NO pvp gear but decent pve gear) in the tunnel, she dropped it, and I had time to get out my orphan (can't in combat) and click the flag. So perhaps defending the flag room is your best bet for this one?
Also got the flag return with Birdfall at 74 after several frustrating games. There are tons of low levels in the battlegrounds right now, so if you're 80 it should actually be a lot easier. You just need to stay close to the flag room until it gets picked up and make sure you have your orphan out. (I returned one flag a guy dropped on purpose but didn't have my orphan out! ACK!) I'd also recommend 80's go for [Frenzied Defender] while there are so many lowbies in WSG right now.