I was disappointed when I first read this, because I'd been holding out the foolish hope that they'd told all the VAs whose characters might plausibly return to stand by for that possibility, but upon further reflection A. given all the uncertainties up until the last few months of game development, there is no way they'd ever do that at this stage and B. I should probably just be glad to learn that they didn't tell him
Aren't the VAs still on strike? Or is that what you were referring to with "... given all the uncertainties up until the last few months of game development"?
I'm not sure when exactly the voice work gets done, or when the hiring process begins, but going by some remarks by David Gaider, is seems like the game would be in actual development at the time. I wouldn't be surprised to know that currently they are still working on bare-bones writing stuff, plot outlines, etc.
That said, if the next game takes place in a certain northern locale like many are expecting it will, then I don't see someone like Cullen being in it at all, even if he's alive, well, married to the Inquisitor, and even if the Inquisitor is in DA4 in some capacity. DAI was the most extreme with the carryovers, but at least they all had a reason to be there and it made sense. Pretty much everyone aside from Dorian and Solas has no reason to be in DA4 if we're going north. And honestly, as much as I adore him, I'm hoping for minimal Dorian involvement. Fresh people please.