Staraptor quickly now if the heat wave will go through, fly away across the bridge while your using the hp flying to get out of the heat wave range, if that would fail and hurt you use an ominous wind to block it and the other hps instead of the hp flying, or use one then the other if that wouldn't work. Then also as you use the hp flying and/or ominous wind start flying across the bridge before anyone else and before it gets hit/broken by the fire punch. So once you fly across the bridge to the tree of dreams, and over any pokemon that are on the bridge pop the Luvdisc bubble imminently, while simultaneously activating your ability, before Slowking can and gain the health. Then when you return to the island if you have an attack left, if the health of the bridge is 15 or less use a wing attack on the bridge, or if the bridge's health is higher then 15 then take it down once you get back before any one can pop a bubble. But if the bridge would be broken before you would make it across don't do anything that involves the bridge except activate your ability.
Also I think that if he says that the heat wave would go over the hps that physicality the hps should hit him still cause there are so many of them that they would either block the attack or all the attacks would hit home via Charazard gets hit by all of the HPs and everyone else would be hit by the heat wave.