I'm having the exact same problems with radeon rx480 nitro+
Last WEG and Lilu version.
10.14.1 installer.
At the end you get the black screen.
I tried the RadeonInit=true in clover.
Nothing. I think is something related to the combo radeon rx + socket 775.
I pluged in the gtx 710 I was replacing and I was able to get video without problems.
I think we will have to mess up with kexts and framebuffers editing. And even doing that I dont know if it will work.
I had an old backup 10.11.5 I tried to boot it with rx 480 and it did... Not Graphic acceleration at all. And it was recognized as 7mb vram card.
