When I got to the Domed City, I did everything to undermine the Outlaws.
I gave the weapon shipment to Alois, I gave the capacitor straight to Erich so Ridley didn't manipulate it. I killed Hunter and the others squatting in front of the city, I gave the fake ID cards to Erich and Alois. I restored communications and made the elex-mech exchange. I set everything so the city would be good to go.

And yet, when "The Abessa Dispute" comes about, the Outlaws take over as if I've given them guns, Ridley takes down the shield because I "helped him" and the Albs massacre everybody.

I can live with not having the perfect ending, but this kind of bug is inexcusable. It destroyed my effort good 10h of gameplay back. I can't go and fix it now.

This quest seems to be bugged for a lot people from what I've read.

I sided with the Clerics on everything and when I returned there were a bunch of dead Outlaws at the bridge. Inside the Clerics and Berserkers are walking around as usual but there's blood everywhere and the "survivors" are talking as if the Albs have taken over the Domed City... which they obviously haven't.
When I talked to Gottfried he even thanked me for getting everything they needed so they could defend the city from the Outlaws.

This bug is very annoying considering all the work I put into getting the exact outcome I wanted.

I had this same issue. I am assuming that since I fixed all the Separitist issues and put them into a position on a positive path that they would not revolt.. but in my game.. they did? It made no sense and was pretty disappointing to find them dead. The raiders I guessed would happened like that and it's what I chose. Abessa was the most disappointing part of the game so far, glad to see its more of a bug and not badly written.

Same here. Abessa is overrun by Clerics because I vouched to keep the spearatists in the city and sided with the Outlaws. I did NOT give the module to Riley though.