I'm leaving this here just in case someone else has the issue I had where you're running Linux and have tried all other solutions to no avail.

It turns out that Docker behaves a little funny with mountable drives, specifically, if your drive is not mounted on boot (i.e. through fstab) the container may fail to find files inside it despite still launching. Make sure your drive is mounted on boot, and potentially change its type if its ntfs, etc. to ext4 or something more Linux-y and that should hopefully fix it.

If the issue still persists and you have the drive mounted, you might need to allow it through a 'virtual file share' - which can be done through Docker Desktop through Settings > Resources > File Sharing and adding the folder/s where your file resides in to the Virtual File Shares section. Details seem vague for the way to do this purely through commandline, so I'm not sure if it's entirely possible...