Well my LS and me formed a party of 30s and one level 29 WHM we won and it was good team work that won it too. I was a level 30 MNK/WAR10 so we had to really on good work.
when i went to do this quest we formed an partially full allaince, with two lvl 50+, a few 40's and a bunch of 30s, killed it with tremendous ease. You should have nothing to fear.