Istredd is frank about Thorne everywhere but in Thorne itself, but he didn't speak much of any of the others. He was mostly focused on the Singularity and then on what they knew here about the Summoned. It helps that Istredd knows that Lucifer and Kyle will report what they found out to each other. They're a very good team that way.

He knows that Lucifer likes to be pet like any feline so he is more than happy to indulge, drawing patterns on his back with warm fingers.

At this point it would be stupid not to. Unless they don't share everyone else's interest in us. But it would be strange to allow Luna and Feywilds to make a claim on us without question. Istredd would have expected them to do so soon after Luna, but they must have thought they had more time. And no one thought the Fey would come out of no where for the first time in centuries.

(Except for the conspiracy theorists. Sometimes they're right.)

I plan on giving Thorne the very barest details, to play along, but I wonder if Nocwich would be so bold. And if Thorne would allow them to speak to their Summoned. Things have changed since the Pit. They did help us recover after the Pit. And that may make him waver a little.