Unable to create RAWDISK vmdk which includes extended partition

[Feline]

System is dual boot between Windows 7 Professional and Debian 9. The bare-metal Windows 7 system is installed on a 256GB SSD which has the system reserved partition, Windows system partition and two data partitions, one of which is a logical partition.

Debian has VirtualBox 5.2.8 installed and a separate instance of Windows 7 is installed within a virtual machine which requires RAW DISK access to the two data partitions mentioned above.

Issuing parted from Debian shows the following (correct) partition structure for the drive,

Disk /dev/sdb: 256GB
Sector size (logical/physical): 512B/4096B
Partition Table: msdos
Disk Flags: 

Number  Start   End     Size    Type      File system  Flags
 1      1049kB  106MB   105MB   primary   ntfs         boot
 2      107MB   41.3GB  41.2GB  primary   ntfs
 3      41.3GB  68.1GB  26.8GB  primary   ntfs
 4      68.1GB  256GB   188GB   extended               lba
 5      68.2GB  256GB   188GB   logical   ntfs 

Issuing the VBoxManage listpartitons -rawdisk command does not give the same results, as shown below.

VBoxManage internalcommands listpartitions -rawdisk /dev/sdb
Number  Type   StartCHS       EndCHS      Size (MiB)  Start (Sect)
1       0x07  0   /32 /33  12  /223/19           100         2048
2       0x07  13  /0  /52  1022/254/63         39290       208896
3       0x07  1022/254/63  1022/254/63         25600     80674816 

It does not appear to have recognised the extended/logical partition structure and has also calculated partition 3 as the size of the whole drive.

Attempts to create a RAW DISK vmdk just referencing relative partitions 3 and 5 give the following warning message :

VBoxManage internalcommands createrawvmdk -filename "/disk/VM System/Raw Disks/Windows Data.vmdk" -rawdisk "/dev/sdb" -partitions 3,5 -relative
VBoxManage: warning: It is not possible (and necessary) to explicitly give access to the extended partition 5. If required, enable access to all logical partitions inside this extended partition.
RAW host disk access VMDK file /disk/VM System/Raw Disks/Windows Data.vmdk created successfully. 

Whilst the VMDK is created it does not map the logical partition correctly. When seen from within the Windows 7 guest, the 175GB logical partition shows up as free space.