We need to move our vm’s which are part of WSFC which are using shared pRDM’s to Pure Array.

For that, you'd probably want to convert from pRDM to vRDM and then storage vMotion. You wouldn't need to use a placeholder virtual disk or vm in that case. That said, converting from pRDM to vRDM might not be possible or you can't take the down time in order to do that. Then your best bet to do it non disruptively would be to do it at the OS level. create virtual disks for the vm on the pure array and then move the data over.