User blog comment:Hawki/Nova Covert Ops, part 2 - Reflections/@comment-72.197.211.140-20160824180726/@comment-58609-20160831235239

Per the above points:

-The Dominion is well aware that the Tal'darim are a separate faction from the Daelaam, this is established in the field manual. The Defenders could have attacked them for any number of reasons though - they're anti-alien on general principle it seems.

-A lot of that is speculation, but I can see why a character like Davis would exist. I think it makes sense for her to exist and to possess such motives. Even if NCO does end with a return to the status quo, it can at least say that it addressed the idea of a "Mengsk loyalist."