The hitbox for the Brand Crystals/Trapped Soldiers is bugged, especially in relation to Mesmers. Mesmers are not about to summon any Phantasms to damage them; instead, I get an "Obstructed" error, even while standing in front of the Crystal. This is true regardless of which side of the Crystal I face. In addition, Clones will also not attack the Crystals.
"Thief? How rude! I'm a Procurement Specialist." -Glenn Gynnafante