You can experiment with this to see by placing a distortion stomp in the x slot on a rig and tlurning up and of the various level values, that includes things like imput sens settings. If these were controlling volume before the speaker sim or before anything else you would now hear that distortion getting more distorted as the level values increases, just like when you plug a guitar into a stomp and adjust the controls in your guitar, instead you’ll hear only that things get quieter or louder. This means that these controls are just controlling the output volume of the Kemper as a whole, they are all methods af accessing exactly the same thing.
Really? Is the Amp volume only controlling the output volume as well?