Moderator: Moved to vSAN
It is a very common issue to not see claimable disks properly when using a vCenter of a lower major update version than the ESXi version e.g. 6.7 GA/U1 vCenter and 6.7 U2 hosts - this isn't supported.
Solution is to update the vC to the same or higher version or create the DGs via the CLI.
Upgraded VCSA to same version as ESXi, Disks now discoverable¬
Great to know that for future.
Also note that from a support perspective it is typically required to have vCenter be at the same version or higher!