Seems pretty simple to me, but there again H-D is populated with simpletons who can't figure out simple things.
1. Find a new bike that the dealership and the customer agree operates satisfactorily.
2. Remove the entire clutch assembly from that bike (not just the plates, the entire thing).
3. Install the complete clutch assembly in your bike.
4. Operate your bike and see if this has cured your problem.
5 If it does, send you on your way and let the dealership ship your complete clutch assembly to H-D for them to figure out (assuming they can).
6. Harley to ship a complete clutch assembly to the dealer to replace the one they took from the bike in inventory.
This isn't something I just dreamed up after consuming excessive quantities of mind altering substances, btw. I actually did a few similar things back in the old days as a field service engineer/rep in the auto business. There comes a time when the manufacturer needs to step up and get the customer's vehicle fixed ASAP, and then worry about what the root cause of the problem is once the customer is taken care of.
Jerry
Btw, we didn't have lemon laws back in those days to motivate manufacturers to do the right thing on a timely basis. These days most states do in fact have such laws, and something as important as safe and proper engagement of a clutch should definitely be covered. If this had been my bike, I'd have been in touch with an attorney a long time ago.