It...will probably be easier to look over everything in the office. There were a lot of files in that box... And there are a couple extra chairs in there, so you can still sit down. If you still need to rest.

[It's said with very doubtful deadpan because he can now see, quite plainly, that that claim was also a lie. If Kokichi could get up and rifle through his desk (and the rest of the main office, Shuichi is sure), then he can't actually be in THAT much pain.]