After some back and forth with Curt and a unsuccessful 30 minute attempt to get the trailer hitched, they sent me a complete top half hitch assembly (really would have preferred just the head assembly). I found a reproducable problem with the jaws; if the plastic kingpin that comes with a new hitch is pulled to the front of the hitch, the jaws will encircle the pin but the jaw half that moves up and down will not drop down until the forward pressure is relieved, then it will drop down. For some reason the trailer kingpin will not allow the jaw half to drop and thus won't lock the pin.
The new hitch head works fine as one would expect. New problem is that after I tested a successful hitch when I pulled away I noticed shavings of the plastic disk by the two bolts on the hitch plate. This is caused by the bolts being a fraction above the plate instead of below it. Currently discussing this situation with them.