It's not as if the Federation-Klingon-Romulan alliance defeated the entire Dominion. They defeated a single isolated Dominion outpost in the Alpha Quadrant. So I wouldn't expect the peace treaty to say anything about Gamma Quadrant territories.
Though Section 31 nearly succeeded in getting the Founders killed, the cure was given to them before the treaty was signed, so I wouldn't expect that to be a factor in the treaty.