Lia was preoccupied with other things while Nyzahr went off to try the mirror. If it goes badly she will be upset. She already has a distinct lack of trust for her. If she really messes things up she will very likely think that Nyzahr is some kind of spy.
At present, Fay and Poljen are restrained. They can use their action to attempt to break free via a strength save, attempt to cut their way out, or try to fight from where they are.
Bear in mind for that last option, speed is zero, restrained subject's attacks are made with disadvantage, and attacks against the restrained are made with advantage.
Just for precision for Dungeon Master, Nyzahr will use her 6 points of bardic inspiration to boost her Persuasion skill, bringing the roll from 16 to 22. Hopefully that gets our guy convinced that "Commander Cyanwrath" proposal is legit…
So we can make an educated decision, what would cutting ourselves out entail. Only give us as much information as they would know… I don't want to make a decision based on too much info. I like the edge of your seat feeling.