He decides not to say that, in the moment, he'd felt very inclined to kill her. He's not sure whether or not the sentiment has lingered. In the aftermath, he'd wondered if there were something more complicated to her involvement, given her apparent relationship with Geralt and the fact that she was coming from the perspective of being a prisoner.

Either way, the semantics of it aren't important to him, so he won't argue the point. He's mostly just surprised that he doesn't seem to care one way or the other. It seems this is an ongoing theme.

"If you are truly so uninvolved in her fate, then mayhap there is no issue."

This is an unexpectedly difficult thing to work with. Given that he has positive impressions of a few of the people in Geralt's in-group, he's been disinclined to cause unnecessary friction with them. Yet, making his stance on things clear doesn't seem to be very effective here. It shows on his face, for a moment - the way he doesn't really seem to know what to do with this situation.

He didn't come here wanting to be an asshole. If anything, he wanted to keep up ties with those in other places. This sort of thing isn't usually his job.

"I only know it would avail me not to make more enemies than necessary."