We gave you plenty of time to respond, you should have qued to join party or joined the xbl party and said "hey let me in to matchmaking party now" or something.
Yes, Paul and Dan are comediens, I didn't originally decide to do the achievement with them they kinda decided that they'd help/watch me do it because they'd both been given matchmaking bans for quitting too many games, namely on the receiving end of the betrayal boot or the disconnection at random due to theirty net connections. I got the distinct impression right from the off that I wouldn't get it with them two around before they done it but if I did do it in front of them then well it'd be awesome to just point out how cool that action is. I never get bored of watching that clip over and over, best achievement ever really imho, unless they come out with one for betraying Kat in campaign for driving like Julian's mother, badly and suicidally, generally at the same time it's why his mom loves to be driven so often.
New weekly doesn't seem too bad either if you can bang in 200 kills a day or so.