TBH, I have no idea what they're going to do in DLCs and I probably should not predict anything anymore... but with the way things are shaping, incessant mentions of Varric and now certain things in patch beta hinting towards direction things may go, it's hard to say whether we'll be getting any Well- or ancient elf- or Dread Wolf-related things in upcoming DLC... Wouldn't be surprised if we'd have to wait a bit more for that.
Just peeked...interesting.
Well, we were told that only some of the loose ends and things we're curious about will be addressed in DLC and there have been a lot of hints about Qunari and/or Deep Roads, and things like The Executors, so I would expect that the next DLC, whatever it is, will only have some threads. JoH felt relevant to Lavellans, especially if yours loved Solas, but it also contained codexes and lore bits and history , as well as other elements that may be further relevant later.
So, even if we're not getting any leads on Solas just yet, I still think next DLC will have some things that add to the other stuff we're all thinking about.
As far as the Well, that would make most sense to wrap up before we have a possible new player character, so that will likely play a part in the final DLC for DAI rather than earlier.