How did he put the rug back?
After he dropped through the hatch?
shareIt was stuck on the hatch.
shareI think the bigger question is how it went undetected for however long it was there. I doubt it was there ten years ago, but it wasn't just ten hours ago either.
Guessing the Senator has a maid. If the maid is worth half the salt a maid should be, she'll move that rug to be thorough when cleaning.
Also, there are clearly traitors in their midst. And enough of them, where we can assume that at least one is going to be smart enough to be looking for such routes, and if you're looking in the garage, which is reasonable, since that's where the (getaway) vehicles would be, that recess in the ceiling is pretty obvious