I am aware of this thread: File output Node not working
However this is not my problem. I have used this file to output to files, but I am trying to use a 3rd scene in order to composite the 1st 2 scenes and output them individually for further compositing in different software later.
The 2 scenes are compositing and rendering as a png perfectly, but the individual scenes will not save as exr's. I just cannot understand it. This should work.
I've checked everything I can think of. It also will not save the renders with the composited layers disconnected. This setup worked in other setups.
I was delighted to find that you can render scenes with different render engines in the one render pass, and I can even composite them in blender - it's all working, but I want the renders seperated to use in VFX software.
Actually - now I think of it I am using 2.92 beta, I will try the release (2.91) where I had this working before. But I'll leave this here in case anybody else runs across the issue, or in case somebody might know what I am doing wrong.