Looking at your post from Blouse's thread, you aren't using my Clover folder as your drivers64UEFI folder is different.
Try this config. I removed the lines for the Intel GPU and Vega 64 (you don't need it to get setup). Keep the Vega GPU installed. I did my initial install with the Vega card and didn't have any issues. I also removed hidden drives (as you need them for the initial install).
How did you create your boot disk? It's daytime here for me in Japan, so I don't have access to my desktop. I'll give the install process a test when I get home (obviously it's been a while since I installed).
I was having a Network speed issue since 10.14.6. Kexts were updated and my speeds are much faster 17ms 400mbps/80mbps. Supposed to be 600 down, but it is a wireless connection that is shared with multiple users, so I'll just chalk it up to those factors slowing it down.
Prior to this I was seeing a latency of 200ms and no speeds faster than 25mbps down.
Also, I removed my Vega 64 settings from the main config in that folder. If you want to use it, it is labeled Config-Vega64.plist
Edit: Updated clover to 5033 as well.
Edit 2: Yup, it was my users in the house. Almost full speed via wireless