Frontier did a great job of modeling the greenhouse effect. 98% CO2 means no polar caps, haze instead of white clouds, and temps barely low enough to support ammonia based life. All this difference within the exact same Goldilocks zone for ammonia worlds, just based on the Atmospheres.
@Agony, I'd love to a screen shot. It's a rare (and massive) moon that can support an atmosphere. I am almost certain that masses were boderline binary, as opposed to moon-primary. So yours should count imo. I found a binary ammonia system to on my first trip to Sgr A*, back when I thought such things were common. Silly me.