[@Stern Algorithm]
Rodias was already informed that Isolde had been [i]defeated[/i] by Morgan, when the ESPER Wings returned to the Chateau minutes before the gorgon. Since the ESPER Wings concluded that Isolde had 'died' from the encounter, as she was turned to stone and lost contact with their mutual mental network, they see no need in retrieving her.

Remember, the ESPERs are essentially mindless puppets. They don't have personalities or wills of their own. They follow Isolde to the letter and, should she not be available, the highest-ranking Bandeersnatch Guild Members would be used as a replacement. They honestly couldn't care less about her, beyond the fact that their combat-efficacy has dropped due to not having her give them orders. xD

You can feel free to mention her if you want, but again, people have already been informed that Isolde lost to Morgan, and given what the ESPERs told Rodias, the current scenario doesn't lend itself to supporting that she's still 'alive'. Even though she is. :P