Premiere Pro guy here, but still a long-time user of Lr (classic and cloud).
I've got some DNG images taken with the Lr Mobile camera that I'm trying to get into Apple Photos as RAW files. The images were taken with various iPhone models, starting with the iPhone X. When snapped, I usually preferred the hdr-dng version to the regular dng version, so I deleted most of the regular dng's.
When I export now from Lr (either macOS 12.5 or iOS 15.5), the few regular DNG files I have export and add to Apple Photos perfectly. The hdr-dng files end up a blown-out white & magenta mess.
For reference, here are 2 screenshots of what the regular dng's look like in Camera Raw 14.4 and Apple Photos.
Camera Raw
Apple Photos
 
Now here is what happens with the hdr-dng's:
Camera Raw
Apple Photos (and in Preview on Mac, and in RAW Power, and in Pixelmator Pro, and so on): 
If I export as a DNG from Camera Raw, I get the same result as exporting from Lr.
I'd be grateful for any help or insight, even if that help starts with, "Hey Stupid!" 😀
Cheers,
Jeff
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