In order to make this work, hardware-wise, you'd need the lighthouses, too.
Is that something you have a source to confirm?
I would like to think that if Quest is going to release a way to hook up to the PC to play SteamVR, they'll be sending all that positional data from the headset tracking to the PC through the link.
This is inaccurate.
The lighthouses scan the room with lasers. The dimples on the Vive and its controllers detect the very precise timings of getting hit by the lasers from the lighthouses and derive their location and orientation relative to the lighthouses.
This is how the Vive supports easily adding Vive tracker pucks to the room to add body tracking to games like VRChat. The lighthouses are passive and don't care that there are more devices to track, as each device tracks itself.
There's a good video explaining it at https://youtu.be/J54dotTt7k0