I'll try to explain the treaty two ways.
The characters, after tracking down Kragadum and Shivala to their lair inside a volcano, were hovering over a bubbling caldera of lava. Kragadum had Edelbrock on a floating disk, having saved him from drowning and burning in the lava after a fall, and therefore at his mercy. The rest of the party flew out to the center to parlay. Kragadum offered his terms of surrender, which involved returning part of that which was stolen from him and the right to not be murdered by hobos. In return, they would leave the Kingdoms alone for as long as each of the PCs lived. (Since Mauril plans to become immortal, this is going to turn out poorly for the dragons, but that's another thing entirely.) The party was in a precarious position, knowing that a single Greater Dispel Magic would have pretty much killed everyone in the party, and two great wyrm reds are a formidable enough challenge on good terrain. So we tried to deal, not so much to save their lives, but to preserve our own. The dragons had been pretty much beaten, so their threat (and thus their adventure) had more or less been neutralized.
I think none of the players really wanted to negotiate, but no one really wanted to throw the first punch that killed the whole party either. So Braden, the one in the party with the highest diplomatic clout (aside from Crebain, who was rebuffed in his attempt), attempted to negotiate with the dragons. The end result was something no one really wanted. The dragons got about 1/4 of their horde back, the Redstone refugees moved onto the mainland and Aruthien sort of got pissed.
Aligindel offered a million gold from their coffers, with the citizenry offering up another 25,000 from their own pockets (out of good will, I hope). When Edelbrock and Braden went to Bhelen with the news that Aruthien had vicariously agreed to this, Bhelen was angry, along with pretty much all of the citizens we met. Inexplicably, Cas offered 750,000 gold from his personal wealth... despite his city being destroyed by Kragadum, his people being killed by the dragons and his son on a special vendetta against the Redstone. He seemed to either support the PCs (though not their actions necessarily) or he really just disliked Bhelen. The remaining funds were offered by the druids of Mastillan from their adamantium mines, and were delivered either as ore or ingots.
Braden, with the magical beer coozie, delivered the restitution. There were attempts to get the dragons to move further away (as far as Avantarra) but the dragons just snarled at that. So, the dragons are effectively weakened and shackled... until they decide to break their treaty.
As a player, not killing the dragons was an interesting solution to the problem and creates a very different world than expected. I like that. It creatures great ground for future plots and stories to take place in the aftermath of the Grand Campaign. It gives Bhelen something to continue to worry about and it ramps back up the easing tension between Barloz and Aruthien. It also might spark a civil war (that was sort of already in the making) in Aruthien. It really shakes things up in a way that killing the dragons would not have.
Mauril was champing at the bit to give the dragons what for. He wanted to tell them off and then murder them in their hidey hole. He got talked down, so he waited quietly and, the moment the teleport block was removed, plane shifted home. He strongly disagrees with the treaty, as does Crebain, and they refused to offer their services to aid in fulfilling the agreement.
He finds the agreement weak and repulsive. He felt that the heroes were in a position of strength and, if bargaining was necessary, it should be have done as the aggressors. They should have offered terms (unfavorable terms, at that) rather than accepting terms. They should have reminded the dragons where they were and what had happened to them. They should have forced the dragons to accept what was offered them and, when this pissed the dragons off, killed them and take everything. Then move the refugees into an appropriate location, be that Alder's duchy, Mastillan or Eregant.
Mauril plans now to go to Lindur, meet with the Oracle there and find out what is needed to defeat the dragons. He then plans to raise an army of fire, magma and smoke mephits, specifically those trained as inquisitors, sorcerers, rangers or paladins. He plans to use a considerable chunk of his personal wealth to hire free companies from Eregant and Aruthien to go hunt and slay the dragons, hoping to specifically recruit Rath's griffon-riding dragon-hunting rangers. (Conveniently, it will be every copper gained from WBL when going from level 19 to level 20.) He will then attempt to slay the dragons, though will not necessarily die trying.
Depending on what he finds out there, he may or may not also develop a vendetta against Bhelen. He'd work on destroying the man politically if he found out that the dragons were Bhelen's doing, essentially.
As a character, Mauril really wants to see the dragons dead. Essentially, Mauril feels that we just left two sentient nukes (who hate us) to their own devices, even funding future endeavors. He doesn't expect the treaty to hold, only creating the opportunity for sneak attack by the very patient dragons or requiring a very expensive "cold war" on western edge of the continent. He does not like this and, if it weren't for Manath being the active front in the war, might have actively lobbied to restart the war and sided with Aruthien proper (rather than just a few free companies).
So, I think that covers the treaty. Did I miss anything?
Pillows are designed for relaxation. If they are fighting, what hope do we have?