It seems like this is a known bug in this version. For now a workaround is manually renaming the disks after conversion to ensure no duplicates occur. Alternatively you could try converting the disks one at a time and verifying the naming during each step.

Before conversion you could rename your disks in VMware with unique prefixes or suffixes that ensure even if the last character is truncated, they remain distinct. For example renaming /vmmigtest.vmdk/ to /vmmigtestdisk1.vmdk/ and /vmmigtest_1.vmdk/ to /vmmigtestdisk2.vmdk/ After the conversion manu...