From what I understand, there is no technical difference between lighthouses between Pimax and HTC. The only differences between any Valve Lighthouses is the 1.0 and 2.0 spec. They are all made by valve with a skin on them. Therefore if your device works with whatever lighthouse version you are running, it should work regardless of who you bought the lighthouse from.
So basically, follow this diagram. If your device is a 1.0 tracker, it will only work with 1.0 lighthouses. If it is a 2.0 tracker, it will work with all lighthouses.
The original vive lighthouses were 1.0, the ones shipping with the vive pro are now 2.0. The pro then logically has to have 2.0 tracking for it to work with the lighthouses it ships with (since a 1.0 couldnt work with 2.0 lighhouses). Pimax is shipping the 8k with 2.0 lighthouses, and using the same logic has 2.0 tracking built in. Controllers should be the same deal for both.
So in theory, everything should be compatible between the Vive Pro stuff and Pimax 8k stuff.