I know exactly how I'm gonna start. I'm gonna retcon the affair between Cordelia and Fia by having it be a setup by a spellcaster who used the infatuate spell.
Here's a breakdown:
Bellacorde invaded Verdemar years back, when Cordelia was a teenager. She and the other survivors fled to Henford-on-Bagley. Years later, they returned with revenge and took Verdemar back.
Recently, after growing stronger and more cunning, Bellacorde hired a spellcaster to "infatuate" Cordelia and Fia, as well as planting the maid in the exact right spot to witness the two in the act.
The affair wasn't fake in the sense that it never happened, but it was artificial; carefully curated to weaken Cordelia's power so they could rule instead.
Cordelia and Fia decide after the one-time affair that they're gonna figure out some way to prove they were somehow incapacitated. They end up finding a library in Bellacorde through a secret passageway (even they didn't know about it, but it also leads to Cordelia's cottage). They notice an out-of-place tome and read it. It mentions a spell to cause irresistible infatuation between two sims, even if they didn't already know each other.
The margins mention snippets of the scheme, and they know they can't leave without it. So, they take it with them back to Verdemar, all of the way to Glimmerbrook, and through the portal to the Magic Realm (the tome mentioned the realm and had directions to it from Ondarion).
So, they talk to the magical sages, who tell them about a guy who randomly visited to learn "Infatuate" and then left when he was done. They don't know where he lives it what his purpose was, but they do know his name (TBD) and appearance, which Cordelia and Fia memorize quickly under the pressure.
Then, they leave for a lab located along the path they'd taken from Verdemar to Glimmerbrook. There, they hand the tome to a scientist, who analyzes the fingerprints. Long story short, they catch the spellcaster, and Cordelia gets off scot-free... almost.
There's one last detail: she and Fia did invade Bellacorde AND steal a tome from the library. Since they had to be held accountable, they got public censure. Basically, it's a strong disapproval and an official recognition of misconduct without losing any freedom or power.
Since it was unlawful BUT also to prove the other party guilty and clear Cordelia's name, they let them both off easily. It's a one-time warning not to do it again, but it's not a full punishment. They of course had to return the tome to Bellacorde and publicly apologize to them, but it's so much better than it easily could've been.