Why did the Dominion surrender?

I just recently finished DS9. I got swept up in the final arc narrative, but after some time I'm a little confused.

At the start of season 6, the Prophets lock down the wormhole, blocking further Dominion reinforcements from the Gamma Quadrant, and I assume communications as well.

Two years later, Odo links with the Female Changeling, either instantly redeeming her by showing her his perspective, or proving the Section 31 cure is the only way for the Founders to survive.

The earlier is unlikely. Odo had linked with her before and wasn't able to change her mind then, and he hadn't really gathered any groundbreaking experiences that would change that. So the FC agreed to unconditional surrender to save the Link from the morphogenic virus, and since we see Odo go to the Founders' Homeworld I assume the Prophets re-opened the wormhole.

But... then what? A treaty has been signed, sure, but the Federation just lost the two crucial pieces of leverage they needed to sign it. The wormhole is open again, and the threat of genocide is resolved. The Dominion has full access to their Gamma Quadrant resources, and the Federation just tried to commit genocide against them.

Why the hell would they respect the treaty? Respecting agreements isn't exactly their modus operandi considering they're willing to eradicate entire species at the whim of one shriveled up changeling. Why didn't they launch another offensive? Did Odo manage to redeem a majority of the Founders (who are so numerous their goo covers the world) so quickly that there simply wasn't time to do it?

Either this ending makes no sense, or I'm forgetting something, and