There are no need any HUB here if you just want to add a USB2.0 to high-speed ethernet chip. You can select any CCGx with Rp terminate chip, and then add a DR_SWAP in the firmware to present Data device role on Type-C port.
For example, CYPD3175, it is simple chip and can support various charging protocol.
This is not simple, I am not familiar with any of your development tools.
I bought the CY4532 kit to demo to see if I could make this work.
I have downloaded the basic programmer for the kit, and now find that I have to download your firmware environment and modify the code on the ARM core as shown in this thread. It would be simpler if you had some pre-compiled code for the more common applications.
What's programming hex you are using? From the thread you have been shared is based on CY4531, which is based on CYPD3125. And you said you are working on CY4532 in this thread, which is based on CYPD3171. It is difference chip. Please kindly notice that.