I'm not an automotive electrician. However I am qualified in UML, which is the language used by Honda to design and prototype the logic in their automotive electrical systems.
Assuming that Honda use push-to-make switches (not guaranteed), the easiest and most-effective option would be to disconnect the rear switches.
The window motors will be actuated (i.e. told to go up and down) depending on messages received over the bus. If there is no input, then they remain where they are. By disconnecting the rear switches you will be removing that particular input, however the system will not realise the switches have been disconnected.
So, as a first step I'd try disconnecting (AND INSULATING) the spades from the bottom of the rear-door window switches. If that works, you could wire in a remote switch to the front to switch them in and out as required.