User blog comment:Gundam Legilis/Destiny In Depth/@comment-31.205.75.38-20160111015256/@comment-31.205.75.38-20160111022528

No idea. I guess if they weren't expecting anyone to head down there and Mercury was there so he gets first reaction but then that would require a) there to be something down there, which we haven't seen evidence of yet and b) a reason why Cinder (who admittedly may have more important things to worry about) or Neo (who'd be even better at the whole disguise thing) couldn't do it, both of which your brought up.

So, I have no idea. Extradiegetic explanation is bad writing or they needed some reason to move the plot along that didn't stretch disbelief and that was all they could get without it being even more unbelievable (a bunch of teenagers getting enough intelligence, within a very small timeframe, to figure out what is presumably a very complex plan that requires discretion and subtlety would be pretty unbelievable and feel very forced).

I guess one could blame Mercury - him lying low last episode did raise some eyebrows, but thus far he's been pretty good at following orders so meh.

Hopefully we get answers next time. Hopefully.