"What's a 'clone'?"
You take your existing can-start-the-Sprinter key to a decent locksmith.
They put it in an electronic box that pulses the RFID chip in the key, and records the key's response.
They then write that response into a new key with a programmable RFID chip embedded.
They then cut that new key's metal to match your existing key.
The new key is a "clone" of your old one. Your Sprinter cannot tell the two apart, it thinks they're both the "old" one.
------compare and contrast to---------
If, however, you went to the *dealer*, they would create a key with a *new and different* RFID chip/response (but the same cut-metal shape)
That *new* response would have to be programmed into your Sprinter so that it allows both your old and new key to start-and-run it.
So a dealer-sourced key is not a "clone" ... it's a metal "copy", but an entirely different RFID response.
--dick