Mount the cloned drive and find it in the File Explorer. Attempt to find the key. If you can't, un-mount and look in your UEFI/BIOS. Another way is to run an admin level Power Shell command>Get-CimInstance -query 'select * from SoftwareLicensingService' and it's there. All this is assuming you never changed the MOBO. If you did, Microsoft can still help. Make sure you specify OEM or Retail Windows type.