Tracking would be possible with any kind of magical bond... that's probably how Nightshade found you in the first place. You still had a contract with the Rose Queen, even if you betrayed it, and the circumstances were a bit dubious.

Maybe it will be easier for her now. I'm not sure. This whole time, I'd been thinking you were protected. [She pauses, trailing off...]

You're very concerned with those two, aren't you?

[It seems more that way, knowing that he made a deal on their behalf instead of just including them along with himself.]