This time in lower level of sewer after using the scaled key. I come
upon the Dragon Prince, he summons an elemental, next round I choose
"Fight" and Caleb is suddenly dead.

This is getting truly annoying. Since this is a fairly tough mob for
me at this point in the game, chances are there will be a summoning at
least once unless I can manage to kill the dragon prince right away.
Seems I will always encounter the same glitch, so I'm at an impass in
the game.

Any word on a patch?