Sure thing.
Before I had both AAPL,ig-platform-id and device-id set to Iris 655 but with a mistake as below
This is incorrect. AAPL,ig-platform-id should be 0900A53E. Anyway, after fiddling with settings again I thought to use UHD 620 values this time.
also, framebuffer-conX was not set correctly followed old settings below
con1-alldata was set with 00080000, which is HDMI. Compared with others, I've decided to split alldata values and start counting conX from 1 instead of 0.
Correct settings are:
AAPL, ig-platform-id == 00009B3E
device-id == 9B3E0000
with framebuffer as:
Everything functioning well afterwards. I did test it with SMBIOS for MBP15,4 and MBP15,2. I do believe with AAPL, ig-platform-id: 0900A53E and device-id: A53E0000 should work as well, followed https://elitemacx86.com/threads/intel-uhd-graphics-620-whiskey-lake-on-laptop-clover-opencore.455 . So, in my case, framebuffer-conX key values were set incorrectly.