4 Channel DNG/TIFF/RAW (RGBI) Imported Images not being handled correctly in Darktable/Lightroom

Describe the bug

I have thousands of scanned images (slides/negatives/positives) captured with VueScan in (64/16bit) RGBI DNG format on a network share. (Images scanned with Nikon LS-9000 and Epson Perfection V850). I have historically been using Adobe Bridge to manage photos and wanted to see about converting over to Darktable/Lighttable). When importing a copy of the directory (as a test to avoid any bugs with image modification) lighttable imports the files, but all show up with a missing image placeholder.

During import I get a flash of 'image xxxxxxx.dng is not available' which is the filename of the actual image file. The same file can be read natively and can be imported/seen in bridge without an issue.

After the import process the exif data on the file does exist (can see the metadata, path, filename, size, etc) but just no thumbnail and when I go to the darkroom tab it says 'could not load xxxxxx.dng switching to lighttable now'.

But can go into photoshop from bridge and works fine there.

If I use individual JPEG images this works as expected. Can Darktable not handle 64bit/16bit RGBI TIFF/DNG files or RAW (gamma 1.0) DNG files?

Steps to reproduce

Import
Add to library. (any directory),
select files to import.

Expected behavior

should generate or display thumbnails of images in lighttable and allow processing with darkroom

Logfile | Screenshot | Screencast

No response

Commit

No response

Where did you install darktable from?

darktable.org

darktable version

4.4.2

What OS are you using?

Windows

What is the version of your OS?

Windows Server 2022 (21H2)

Describe your system?

Supermicro X10DAX
Dual E5-2667V4
256GB ECC Ram
Windows server 2022 (21h2)
Nvidia GTX 3080TI

Are you using OpenCL GPU in darktable?

None

If yes, what is the GPU card and driver?

No response

Please provide additional context if applicable. You can attach files too, but might need to rename to .txt or .zip

No response

Start by reproducing the import in darktable 4.4.2 on Windows with the reported 64/16-bit RGBI DNG, TIFF, or RAW files, then compare the behavior with JPEG imports. Trace the import, thumbnail, and darkroom-loading paths using the reported missing-image message. Done means the affected files produce thumbnails in lighttable and open for processing in darkroom.