I actually went 0/17 on this mission. First, I kept trying with 2 other buddies I did the other missions with. On the way, we picked up other people for this mission who tried it with us everytime. In the end, we were 5 people, so we always ended up looking for that extra person (for this mission only). Needless to say, we always wiped... several times. A few times we managed to get Alexander to 40%HP, only to run out of time. We tried different setups, but generally we were:
BRD SMN PLD MNK RDM/DRK/BLM.
I was the BRD, and the RDM alternated among RDM, DRK and BLM. We tried every night for like 2 weeks.
One day, last week, I logged on, and someone was shouting for this mission. Since they were 5/6, I told them that if they needed a BRD with Storm Fife, I'd like to join. They invited me. Their RDM had left them, and they thought it would be a miracle if we won without a dedicated healer. The setup:
BRD SMN BLM NIN DRK MNK
We didn't wipe on the BLU, so that was good. We wiped once with Alexander, but we got back up, and beat him with about a minute remaining. I played Double Paeon for the NIN, and ballads for the mages (with Storm Fife, that's 5mp/tick).
We couldn't believe it. >_<
So I finished that. But I promised myself I'd still help my other group finish it. We tried that same night, and we wiped... again. They got fed up with dying all the time, and they said they'll try again at some future date.
In any case, if you contact me in-game, I could give you the names of the people who need this mission. And I can tell them about you.