Cannot use Aqual/Eternal Quintessence in Molten Core

[cpevors]

Describe the bug
After killing bosses in Molten Core, we must use Aqual or Eternal Quintessences on the Runes of Warding on the ground to douse the runes and, ultimately, summon Majordomo Executus (who, in turn, summons Ragnaros). However, every time I attempt to use the Quintessence, I'm provided the error that I'm "out of range," despite being right on top of the rune.

As such, I'm not able to progress through the raid, as Majordomo never spawns.

Game Server
CMaNGOS TBC

Hermes Proxy Version
3.10.0