When I process ProRAW, the photos display correctly in Photo AI but once exported, you lose the embedded Apple ProRAW profile in Lightroom making the images to be at least 2 stop too dark.
When I process HEIC from my iPhone 13 Pro, Photo AI process them fine but the resulting HEIC cannot be imported back into LR
Firstly DNG files exported from Photo AI carry their own profile, DNG files either exported from or updated from Photo AI are NOT RAW files as RAW files, in a DNG wrapper or propriety RAW such as CR2, contain sensor data.
For supported file types look on the Topaz Labs support site:
Note you can use Apple Preview to convert your HEIC files or you can set your camera to produce JPEG rather than HEIC.