Ah, S-Cells have come up. S-Cells have not been so much decanonized in this quest as they are irrelevant.
Which, honestly, isn't much of a change from their status in canon.
Let's be clear: S-Cells are basically midichlorians. They're a special microscopic cell which only Force users Super Saiyans have in any relevant amounts, which allow one to use the force access the transformation. Like midichlorians, S-Cells were introduced after literal decades of the franchise muddling along acceptably without them, as an attempt to create an explanation for a phenomenon which didn't really need one. They are a solution, desperately searching for a problem and finding nothing.
Furthermore, they possess virtually no presence in the canon save for their mere, pointless existence. They aren't needed, they're used poorly where they're used at all, and they're boring. My reaction to them, much like my reaction to midichlorians, was, "Oh, I guess that's a thing. Okay, I guess. Doesn't seem terribly necessary. Does it change anything? No? Alright, I'll just wait for you to stop talking then, Akira."
S-Cells are pointless, and unless they make themselves relevant, I intend to ignore them. They're not decanonized; they're there, even if they don't really do anything other than the obvious. I just don't intend to grant them any more relevance than they've earned.
Which, in this case, means never mentioning them in the quest itself, and this being my final word on the matter.