So, either the authors camera is not yet supported by Lightroom Classic, or the authors Lightroom Classic is older than required for the camera to be supported, or the preference file is corrupt. Ok, forgot one inquiry for the author. Fairly sure, if the photos were already imported, the thumbnails would show a preview, although, grayed.
Have you considered resetting the preference file. The preference file can get corrupted leading to buggy behavior. Resetting the preference file is basically relocating or deleting the preference file. Upon start up, Lightroom Classic would then create a new preference file. Note that many settings will get reset ti defaults. A corrupt preference file will survive uninstalls, reinstalls, updates, and upgrades.
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