You're saying that Sorceress as a class in particular cannot use the rune to save Shadowheart?
Sounds like a bug rather than an intended feature to me. The whole point of the key, the chest and the rune is to provide the player with a guaranteed option to save her incase they fail all the other checks, such as the Barbarian pod smash.
No the sorcerer and wizard had options to feed the rune into the pod without getting into the chest. I hope thats still in and they can do it without the tadpole use. I havent been able to check in game yet.
