Nvidia Shield/ Shadow Cloud - Virtualhere Hub issues

Hi there,

My setup is a Shadow Cloud on an Android TV Nvidia Shield. I have installed Virtualhere Server on the Shield and the Client on the Shadow PC. But the latter cannot see the Hub. It keeps searching every 30sec but no luck on finding it.
What I've tried so far:
I have opened the ports 7575 and 7375 on my router (I checked the port forwarding and they seem to be blocked according to canyouseeme.org, but my ISP said they are not blocking them).
I have tried specifying the hub with the host IP address with both the ports above mentioned (**.***.**.**:7*75)
I have reinstalled Bonjour on the Shadow PC.

Have taken the risk to purchase an Android license thinking that would solve the problem but unfortunately, it didn't. I am aware that the Steam Link app has integrated Virtualhere but opening the Shadow through it seems too laggy and I'd rather use the Shadow App directly with fewer steps.

I really need some orientation on this, I do not know what I am doing wrong. I am lacking in ideas and close to giving up. Could someone shed some light?

Thanks in advance for any help!