The flurry of movement is not unexpected. Geralt remains out of the discussion now that he's said his piece—his only reason for coming in the first place. He's used to investigating alone, and while he's no qualms approaching Jo or Castiel or even Dean's brother on his own, he's disinclined to step into the matter as any part of a team effort when his mere presence increases the tension by several notches.

They can come to him if they want him or need him. He's made no secret the knowledge he holds or the connections he's made in this sphere. (Mostly.) Nor his willingness to help Dean.

Besides. The only solution foremost on his mind is sending the curse back, through the Singularity—not unlike how Ciri sent Voleth Meir back—and that is, in his mind, not a solution he wants to propose. No other potentially has that level of control over the Singularity. Abraxas would look much different if they did. Only Ciri does, and she is not a tool. She never will be. The Wild Hunt is still out there, circling. Waiting for her to open the door.

So it's in the midst of conversation that he catches Dean's gaze, then slips out the door. Dean can find him in elsewhere in the bunker if he wants to talk further. Geralt isn't one to overstay his welcome without good reason—though he does grant Castiel the briefest eye contact on his way out. An acknowledgement of the angel's earlier gesture, when he first came into the room.