Agreed !! But if you listen to the video very closely, especially at the point they bring the camera down low, I think what the OP hears is the typical tapping of the clutch basket.The OP didn't give any description or detail as to what sound he thought might be "abnormal". If it's the well-know whine of the ST engine then the shop didn't explain it was a normal sound. It's not much of a stretch to consider the shop may never have seen (let alone heard) an ST prior. More info is needed — if macmanus ever replies.
Many folks unfamiliar (including Honda dealers!) are not familiar with the sounds.