If it is then it's bug. I think it can proc because Your healer using cleansing ritual morphed to dealing dmg which are DoT or he's using shards which also provides DoT dmg.
puffytheslayer wrote: »there is a slight delay between the meteor being procked & it hitting, so i can complete a heavy resto attack, and 1 seccond later mob gets hit by meteor, the delay is even greater in PvP which can lead to confusion over what does & doesnt proc it.