So what if we return to the status quo when Urth finally betray us or something? It's only three turns. Three turns is enough to find information and make decisions on how to best undermine Urth.
Here's a little bit of speculation of what Urth could do.
1) Continue relations with the Maradysh. Seduce 1 male member with blood ties to the Royal family
==> Urth now has the male blessing
2) Make serious inroads in peacefull relationships with the Barbarian Maradysh.
==> Cause a peaceful split, or even a renewed break of the PU. We can not militarily intervene due to the peace treaty
3) 75 years worth of reproduction. Urth's immortal daughters no longer number in the hundreds, but now make up the as much of the Caradysh population as can be sustained
4) Make proper prepations to ascend.
5) Deal with whatever bothers Urth, allowing him to focus all attention towards us when hostilities are renewed.
MAKE THAT SACRED FOREST! It'll help us see just what Urth pulled to twist his forests and we don't get terrified at trees anymore. Win-Win!
This is a bad idea. In a war, we can't really afford to spend all resources on a fanciful pointless project.
So all in all, it's not the GM fault it ended up the way it did. Oshha did roll for other civs aside from us and Urth just rolled really well.
I'm not sure Urth rolled that well. It's just us having an information deficit. Specifically, we were not aware of :
1) The extent of the Maradysh internal divide, and how close they were to violence.
2) The extent of the infiltration of the Maradysh.
3) The amount of actions Urth could take per turn.
4) The presence of a value that Urth could exploit to rapidly trigger a war with the Lowlands, and create an alliance of convenience.
Specifically, I wouldn't have had a problem with the Maradysh being triggered into a civil war. I didn't expect the infiltration to be so complete, but it's not too suprising.
What I had a problem with is that a value that was previously not mentioned, popped up to trigger a war declaration, and was then easily shattered by Urth to allow for the alliance to occur with the barbarians. Oshha has brought sufficient explanation for that (which you can find earlier in the thread), but the impression it gave was bad.
Edit: Speaking of which, we need to be carefull to ensure that that delibating belief doesn't cross over to our main society. It would be terrible if our entire society started believing Urth had mind control plagues.