its very hard to do a straight pickup group, I found that after about my 2nd group I got together. For one, none of the people are used to the other's playstyles, which is key IMO. I really feel bad for the people that keep trying and trying and trying to get it doing this. Seriously, its a major waste of time doing that. You really have to have friends you know or a guild, or something, to get this done. unless you are VERY lucky to get the right people. Mages are very useful strictly because of their pets and their banishment, so really you get 2 people out of one group slot. The more mages the better, but I found it difficult to even get one. Druids are also helpful because of banishment and their ability to play backup healer or nuker or whatever. If you can get your hands on an AE taunter tank, (AE taunt is an AA class ability if I'm not mistaken), this is because it will help to keep the aggro on one person, in the exe trials you have to LAST, if your cleric is anywhere below 60 in most cases, all the mobs will start to give him/her some major lovin'. The main idea is also, you need somewhere near about 700-800 dps to safely do this trial, because you have to kill 4 waves of 4 mobs, with each mob dropping in 30 seconds minimum, I think the first wave you have 40sec for each mob, I may be mistaken though. Either way, you need lots of DPS.
Make sure, because as us bards, we serve a great purpose as either damage shield if you can pull it off well, or ae slows, both of which really get good at 62, but once again that creates the problem of aggro. Try to stay positioned in such a way that you hit the mobs with your songs if you go the ae slow/dot way, or you'll get creamed in no time. The mobs usually hit for about 250s.
But, if you decide not to do it this way, and get lucky, I had lots of help from the top guild on my server, I have a bard friend that came with some friends and we took it down in short order. of course they were all 65 or thereabouts, and it was easy. This was after about 15 tries of my own, tying to get groups together, sending out tells to people constantly, several nights of nothing but the trials. My heart goes out to the people that are nearing or past 50 - 100 tries for this. this was the most frustrating thing I've ever had to do in EQ, and I was pissed. Anyway, it was worth it now, the exp that is possible, is simply amazing. Keep with it, and try to get friends that you are familiar with, pet classes are a major plus, and just take everything I said here with a grain of salt.