I assume, because the skald dmg add and then a dmg add charge or proc are considered to separate dmg adds kinda like how you guys just changed the dots. well, in this case, the charge one [Heat] and another proc one I'm using [matter]. Aren't stacking I assume this is a bug but I could be wrong here's the video.
wont let me upload but hes the link https://youtu.be/K0vB-9ATZjs