I've done this fight several times now trying to get the darned pants for my buddy's monk. He brings his warrior to tank and his brother comes as a black mage to sleep our groups, me as bard. The trick with the boss is to have everyone stand apart and far away from the dragon. That way the tank can dance around all he needs to and won't point the dragon breath move towards the others. And the toxin spit is either random or goes to the person who is #2 in hate...i'm not convinced on either one, because usually it seems like he's locked on to someone multiple spits, but i used quelling strikes to get to #3 on hate list and still got spat at three times in a row.
To the OP your WHM was just talking rubbish, ballad doesn't pull enough hate to make him turn like that. In theory at least, he probably spat at you because you were highest on the list after the tank. :O
(You can tell by having the enemy targetted and looking at names in the party list- you will see a #1, 2, 3, or 4, or the letter A. A is who he's currently attacking, 1 means you're about 1 attack away from being A or he is currently randomly targetting or targeting someone not in the party, and 2/3/4 is everyone else in that order. And they have a lil bar to show you how close you are to the next # up.) Just have the tank move the dragon around so he steps off of the pools of toxin as they also heal him in conjunction with hurting you. Make sure as your party members get spit at they try to stay on the far side from wherever the tank+dragon are, using up all the free space they can on the ground over there. That way the dragon is less likely to walk in that stuff. D:
____________________________Currently Playing: FFXIV:ARR Lacaan Vasiim:Cactuar Free Company:Cactuar Corp<CCorp>
If you need a bard to get "good exp" in a merit party, you're the weakest link.