1 - From my original post:
If instead of connecting the hard drive through a USB hub I connect it directly to the mac, I am able to connect it to the guest OS like any other USB device.
2 - I've reproduced this issue with hard disk formatted in NTFS and HFS+ (I have Paragon HFS+ installed on the guest Windows OS)
Additional information: This has been reproduced with both a disk that has multiple partitions and a disk that has a single partition.