I am not surprised at all that you cant expand this vmdk via the UI.
At the moment change block tracking is active while it is declared as very old virtual hardware.
It uses the optional
ddb.adapterType = "lsilogic"
which contradicts the IDE-geometry
ddb.geometry.cylinders = "2130500"
ddb.geometry.heads = "16"
ddb.geometry.sectors = "63"
The size of the flat.vmdk is not alligned to full MBs
which may be another reason why the UI cant expand it:
RW 2147543103 VMFS "DCROWN-flat.vmdk"
size in MBs = 1048605.030761719
To expand this vmdk stop the active backup job and delete all ctk.vmdks.
Then remove ctk-entries from the vmx and use this vmdk descriptor:
# Disk DescriptorFile
version=1
CID=12345678
parentCID=ffffffff
isNativeSnapshot="no"
createType="vmfs"
# Extent description
RW 2147543040 VMFS "DCROWN-flat.vmdk"
# The Disk Data Base
#DDB
ddb.adapterType = "lsilogic"
ddb.geometry.cylinders = "133678"
ddb.geometry.heads = "255"
ddb.geometry.sectors = "63"
ddb.virtualHWVersion = "8"
If I had to expand this vmdk I would use dd and write a new descriptor.