I took a closer look at this. My TV (Sony A8H) reports that HDR10 is playing, but it is clearly not - the picture is awful, the way that non-tonemapped screenshots look.
So, unless the Apple TV is just not switching modes correctly, it seems that Infuse is correctly detecting the HDR10 layer, attempting to display it, and failing to process the metadata. I tested this on my parents’ Apple TV running Infuse, and had the same results. I have also tested multiple files.
This only seems to be occurring with dual-layer. Single-layer DV and HDR10 work excellent as always.
I would really appreciate some help with this. Thank you!