After a bit of head-scratching he thought about repurposing the four unused wires on one of the RJ45 Ethernet connectors. This would allow him to interface with the necessary signals and still ...

So, being the handy guy he is, he built his own. Starting with an Apple MiniDin8 Male cable, he cut off one end and attached the wiring to a RJ45 connector. That got plugged into a modular adapter ...