I think it's ok that your T doesn't have all the answers. Even an expert in dissociative disorders isn't going to know every single thing about it or about their client.They are not living your individual, unique experience to fully comprehend. They can guess by what they've learned but they definitely cannot know it all.

That being said,what do you think the thoughts are and why do you think they've changed? That's what matters.

All your answers are already inside you. You just need to keep working on looking inside to find them.