Point to Tadashi for that; this is a matter of poor coincidence, then. The burden is on him, then, to solve this mistake, and he's just starting to turn away when Tadashi makes his outburst.

And he goes still.

Oh.

Taken so aback, Callaghan can't find a response, only managing to look back towards Tadashi with an expression somewhere between baffled and incredulous. And...perhaps a little pained, because it's clearly hit a nerve of some sort.

"I..."

How can he even respond to that?