Nice little write up. I have a few suggestions.

For Boss 1, while the bombs will self destruct and need to be burned, they can be stunned on their path. I wouldn't really suggest you to do this as a tank, but a melee DD can be made aware of it to get some extra time of DPS on them.

For Boss 2, as mentioned, there isn't aggroe table. I'd suggest the tank handling/spawning the bombs. While the boss seems to move around in erratic patterns, if you are unsure of where to place the bomb, the tank can easily just eat the damage while holding it. This guarantees the bomb hits, and doesn't put the DD in danger of death from bad timing.

For Boss 3, we just kept the boss literally in the middle. Melee DD stays on boss, one ranged DD just fights boss on a rock until the worm needs to be fed. It was pretty tank and spank with that method. We tried moving the boss around but the melee DD takes a lot of unnecessary damage often times, since it is hard to see the worm which will take a good chunk off the DD if hit. I'd be cautious in telling DD to run by you, I'm pretty positive he cleaves, and that mixed in with the add focusing on the DD will be enough for a KO pretty quick. If the DD can do it safely its a nice suggestion though.