But technically, the glasses could see through the wall. We've already had 2 updates, Liz could fix the glasses and add an invisibility detection feature to them. Liz knows about Inoda's abilities. The fact that Asuna is following the invisible member with her eyes confirms this. I think it's a CG from Kirito's perspective. In the memory room, Fujino will add CGS from Asuna's face, in which Inoda is fully visible, as if we were a spectator wearing glasses.
I agree, and I also think that the glasses are a separate gift from Liz for this event, but for what purpose? Asuna noticed and just took them for herself, or is this a hint from Liz that Asuna and Inoda's sex in the game is now easy to detect.