Auto Render Caching Fails on Nested Fusion Clips

I have a fusion clip within a nested compound clip.
caching within he compound clip doesn't seem to work at all and on the main timeline the compound clip tries to cache and I see the red line turn blue on parts of the clips but then it give up and the whole clip turns red again.

same issue here. I'm seeing this on fusion clips and also on compound clips (not fusion)

so i found a workaround.

i use transparent .png files with aspect ratio crops and when i added one on the track above the compound clip the timeline rendered and played back fine. i would imagine that "dummy clip" like a transparent png or adjustment layer with a zero opacity effect could work the same.