Use the voltage before the diode to detect which USB C is upstream. To then get 5V to the VBUS of the downstream port, use a switch which "bypasses" the diode of that port.
I would like to better understand how this part can seemingly be used for both upstream facing port versus downstream facing port applications (if it can at all). From a USB HUB perspective, the 15k ...
The screen has one upstream and two downstream 10Gbps USB-C ports. Not only does the screen have a USB-C hub function but it can also pass through up to 85W for charging via one of the ports.