Hi! Sorry for the late response, but it's because you, before we updated this file, probably downloaded the old version of Knee Deep. When you went to search the game up in your files again, you probably found the old version and clicked on that one. You downloaded the old version and now the new version, which is why you have two .exes. Nobody has reported getting this error before, and this reason is the most plausible one I could think of!
Just in case it feels familiar to you, the old Knee Deep game's cover had Anthony (blue-haired) lying down with blood on him and a yellow game page.