Thosha
Without the Embassy, i still get the best outcome in Gawnfall for everything except Ardford Ban, which gets the 2nd best result (ardford open yes, but not perfect result - same as the walkthrough).
Keep in mind i didn't just remove the Aram Embassy - if thats all i change, the result would be quite bad like you said. I instead get a minor Aram score boost by a previous decison: use the magical charges against the Fucklord in Aram (instead of Zirastria) during the Erosia Prelude. This boost is required to keep the best results, starting Gawnfall with Aram score 15.
The calculator file above should show how it works