[The question surprises Grey a little, since he was bracing himself more for Manabu to be woeful about not being able to come. But he's able to answer easily enough.]

That's unlikely to happen. Any witnesses from the lab will be expecting to see Rezo; the change in my hair color, wardrobe, and demeanor will throw them off even if they're already aware that the Rezo lookalike isn't actually blind.

[Okay, so maybe that doesn't answer Manabu's actual question...]

People see what they expect to see.