Can't trigger Solas's conversation in the Fade

I'm having the exact same problem.  My first inquisitor triggered this fade conversation without issue, but later ended up with a bugged world state import.  So, I restarted with a new inquisitor and encountered this bug.  However, I have high approval from Solas, all I still only have the options to ask about him or ask about Corypheus after the move to Skyhold -- so it's not an approval gated conversation.  All of my other companions' post-haven cut scenes have triggered without issue.  For both cases, I'm playing a Qunari male, so it is not related to a romance either.  I really don't want to start a new character again!  

Stupid bugs :catsad:  It makes me wish we had access to the full developer's console for the single player campaign (I understand that this was likely disabled due to potential cheating in multiplayer... *sigh*)

A lot of companion personal quest progress is tied to approval, and it's possible that the disagreements you refer to have prevented you from reaching the appropriate approval value at this point.

If you haven't done them yet and are familiar with their locations, activating the elven artifacts could give the approval boost you need.