Not sure about the candle specifically, but in 6.1 there are still a ton of broken tooltips. Int trinket from Darmac for example also triggers from heals, where the tt says "attacks"
You will find that most healer trinkets say "Triggers from attacks" in the tooltip, even spirit-only ones. ALL of these trinkets trigger from healing as well, but it says attacks in the tooltip to "promote healers DPSing in downtime" (at least that's what I interpret it as). But ALL trinkets that healers would use, do trigger from heals. Despite the misleading tooltips.
I don't know why they don't say "triggers from attacks and heals" in the tooltip to stop confusion. But, there are still tooltips that are bugged - like the "Oralius' Whispering Crystal" was until 6.1 (they hotfixed it to give 100 stats instead of 200). But I do believe the Everburning Candle, has always been 10k in the tooltip. (I don't know for sure, as I don't have one myself) but I have always known it to be 10k. So it was one of those "we hotfixed it but didn't update the tooltip until the next patch" like the Whispering Crystal.