Belt breakage, even with the latest narrow belts, is not a common occurence. As for the torque statement, no stock H-D has anything even approaching the torque necessary to snap a belt. There are plenty of heavily modified bikes running stock belts with no breakage issues.
Common causes of breakage are misalignment, improper tension, and foreign objects being trapped between the belt and sprockets. Then there is the possibility of just getting a defective belt from the supplier. Have the dealer closely inspect the sprockets for abnormal wear, sharp edges, etc., and then make sure the alignment and belt tension are set properly. You will need to have the new belt checked and readjusted after 500-1000 miles.
I'm not familiar with the current springer setup, but the older versions had to be maintained, cleaned, and lubricated religiously to reduce noise and harshness. I wonder if this has anything to do with your front end issues? Hopefully someone with more Springer experience will chime in here.
Jerry