I can't tell you for sure what happened. However, since the delta files are gone it should be safe to assume that the snapshot cleanup process has finished and the vmware-cmd command may just wait for a call-back that will probably never come due to e.g. timeouts. I'd go ahead check the VM's .vmx file to see whether this was updated properly with the base .vmdk files and then kill the process. If you want you may also take a look at the VM's vmware.log file which should contain entries about the snapshot consolidation. Don't worry too much about the .vmsd file, this is just a text file which contains the information shown in the Snapshot Manager. If all snapshots are gone you can delete this file.
André