dont know what temperatures the blow dryer reaches. Too hot = 60 or more degrees celcius. This could vaporize at least some of the dmt away.

SWIM knows that around 40-50 degrees celcius is when the water starts getting too hot to touch. So SWIM heats up water to this point where it just gets too hot to touch, turns the fire off, puts the solvent in a glass which already has the dmt in it, submerges the glass in the warm water (without letting the water come in the glass of course), leaves for a min or so, moving the glass in circles to make a movement of the solvent and help redissolving.

SWIM would never ever keep the gunk. What he does is add another, say, 5ml of warm naphtha to pick up any last rests of dmt that might be in the gunk, but he definitely throws it away after that.