I have a Smarty for my '02, but my understanding is the programming is in the smarty programs software for the high idle, 3-cyl is part of the ECM measuring the inlet air temp. But that makes the Smarty VIN locked. As soon as you return to stock the high idle is not in the stock program. Not positive about this but my truck is rarely in the conditions where the 3-cyl idle would be needed.
The dealer should have the cable. It is the normal OBDII connector that connects to the Chrysler system. If they can flash the ECM software then they can enable the high idle and 3-cyl. I think it is dishonest for them to say they flashed it yet didn't have the right cable. I would try another dealer or call Chrysler customer (no)-service.