Yay, got it all working with the Onn 4K and the Uray encoder! Pretty slow to wake and start the NBC app then have the app start the stream, from what I've seen it's about 20-25 secs total. That's fine for recording which is all need, don't care about live. I'm using H.265, 1920x1080@60fps, 8k VBR, MPEG-TS.
Here's my pre and post tune scripts for anyone curious, I force close the app and put the box to sleep after a tune which is why the app takes longer to startup I'm sure.
prebmitune.bat
@echo off
set IP=192.168.1.94:5555
c:\platform-tools\adb connect %IP%
c:\platform-tools\adb -s %IP% shell input keyevent KEYCODE_WAKEUP
rem c:\platform-tools\adb -s %IP% shell input keyevent KEYCODE_HOME
stopbmitune.bat
@echo off
set IP=192.168.1.94:5555
c:\platform-tools\adb -s %IP% shell am force-stop com.nbcuni.nbc.androidtv
c:\platform-tools\adb -s %IP% shell input keyevent KEYCODE_HOME
c:\platform-tools\adb -s %IP% shell input keyevent KEYCODE_SLEEP