Kheldian Doppelganger: Form Shifting Bug?

I've noticed this on several occasions notably during the Hero tip Miss Thystle's Plea and the Hero Morality Mission The Unusual Suspect but in other instances involving the Doppelganger enemy also... I have noticed it using my Tri-Form Peacebringer.

I could be wrong about what's causing this to happen, but it seems as if every time the Doppelganger attempts to shift forms, it is turning into a Longbow Enemy instead of a Dwarf or Nova. It is not an isolated incident, in fact it's been a regular occurrence.

Additionally on the morality mission mentioned, Doppelganger will shift into a Longbow agent, and during the dialogue at the end the picture displayed will be of that same Longbow agent rather than of my character.