I agree - not much will be achieved treating only depressive symptoms and leaving the PTSD untreated when PTSD is the root cause.

Complex PTSD has some good treatment guidelines on the Institutue of Traumatic Stress Studies (see link on my profile). Obviously, it does not include going straight into Prolonged Exposure.

Recent research in PTSD has included a lot of the Dissociative subtype (although obviously all PTSD has dissociative symptoms, such as flashbacks). The dissociation subtype is characterized in the DSM as involving derealization and depersonalization, and hopefully we will now see treatment tailored to this form of PTSD more often. Not all complex PTSD would be classed as Dissociative PTSD but much seems like it would be.

Ruth Lanius in particular has done excellent research on this, especially from 2012. Brain imaging showed different responses in the brain for this subtype, compared to "regular" PTSD.