Once we create a vm and after that if rename VM name the .vmdk file will not be renamed automatically.
I would recommed to rename ths file and the VMDK as it is one time job Check the below KB which will guide to to rename the vm files and vmdk
Renaming a virtual machine and its files in VMware ESXi/ESX
Request u to help me with the script so that i can identify vmdk files which are actually mapped / not mapped to a VM.
Take a look at Orphaned files and folders – Spring cleaning or RVTools or Find Orphaned VMDK's