You can't add a partition with v4 - it won't recognize it, and, if you ever remove 4, it will remove your new partition. Also if anyone ever has to fix your v4 install, that will remove the new partition as well.
If you are indeed on 4, best to decrypt, image and then start again.
Are they decrypting it, or are they disabling EEPC?
You still can't clone the disk and add a partition if EEPC4 is still active (if the boot code is there) - it needs to be completely disabled (no pre-boot at all). Then you can treat it like a normal drive.