This covers all wipes and apparently ignores stats after 3 deaths.
For Borer Drill, healers can be forgiven for taking some damage from it as they quite often need to choose between standing in fire for a short time or restarting a hard cast which could leave someone dead. Melee taking damage means they are too close to the boss or a ranged is positioned behind them.
For Ricochet, melee shouldn't take any damage from this, either a ranged is stood behind them or they are positioned too close to the boss. I have no idea how hard this is to avoid for ranged, but the difference between Toban and the other ranged means Del and Gran could do with adjusting their coping strat a bit.