If he gives you guff, have him send you a sample clip of the frame size he needs to deliver, then open it in VLC or Switch (or Premiere) and check its Properties; then copy those into ME.
Ah, the great 2018 update! It broke A LOT of things, mostly (I think having to do with QuickTime codecs.
I’d suggest posting screenshots of your settings and letting the community have at em. I have major problems with PPro/AME’s handling of ProRes, and had to reconfigure any presets that use it.
And for some great humor, check out my posts about what the 2018 update did to my QT XDCAM media…
Do all Windows computers have Quicktime for Windows? I doubt Windows Media Player (or whatever they’re calling it on Win10) plays ProRes files without a little help.