Estinien takes it in hand - he knows that, technically speaking, a person could create something like this with the flick of their wrist in this place, but it's clear that's not what Jaskier has been doing. He has the grapes, he has the signs of legitimately stepping on them... and the bottles own relation to what he's told Jaskier in the past is outright touching.

It's easy to make out, within context, and Estinien doesn't know what to do with it at first. Jaskier clearly isn't upset with him, for him to do something like this, but it only makes Estinien's heart sink to realize it. After all, it means that he is likely uninformed.

"You have my thanks," Estinien says, though in a subdued tone that suggests deeper thoughts are lurking in his mind. It's a stock phrase, but there's meaning in his tone. He appreciates it, even if he is unskilled at verbalizing these things.

He looks away.

"But I would not lead you astray. You... should know that I and your comrades are in conflict. I attempted to make peace, but in coming days, I cannot promise..."

He's making it sound very dire, but in truth, he doesn't really understand it at all.