Obviously the only reason you need
a NTFS driver for Mac
is that the drive is formatted NTFS -- you can verify this be right clicking on the drive in the finder snap getting info - the format is there
as to why Toshiba gave you incorrect information you would have to ask them -- it is true that both Macs and PCs can read NTFS drives as long as the Mac has the special NTFS drivers it is also true that the Photos library can not be stored on an NTFS drive - it must be only on a drive formatted Mac OS extended (journaled) as you have found.
You do not have to get a new drive - you can reformat that drive
You either need to get another drive properly formatted or use Disk Utility to erase and reformat this drive for photos to use
You can purchase correctly formatted drives - Other World Computing and Apple sell them as do others I'm sure - those are the only dow drives I use - and you can reformat any local drive using Disk Utility
and if space on your Mac is an issue another option is to use iCloud Photo librarywith optimized photos on your Mac
LN