I think if they were concerned with hardware multiboxing they would have mentioned it specifically.

Also, there are hardware solutions that don't simply rely on a switch distributing outputs to multiple computers via software replicating input. Before another user on these forums posted a link to a cheap switch my solution was going to be creating a makeshift keyboard on a breadboard each key would be wired to an input pin on several different Arduino microcontrollers. The Arduinos act as a keyboard and sends the keypress to the computer. This is how a normal keyboard works - a microcontroller processes the signal from the button(s) you press and send it to a computer. With 1 keypad you can control as many outputs as you want without any software replication - the replication occurs at a physical level where a voltage is sent to multiple chips with 1 keypress.