I've attached a recreated descriptor file.
However, this won't help much due to the low disk space.
According to the descriptor files, the VM's disk has been thin provisioned, i.e. will most likely grow when you try to delete snapshots, so don't try this at the moment.
Please post the output for ls -elisa, as this will show not only the files' provisioned disk space, but also the used space. Base on this we need to find out how to resolve this issue.
How much free disk space do you have on the other datastore? I'm asking to find out whether it is an option to clone the virtual disk from the command line.
André