Picked the car up from the local Hyundai dealer. They were unable to duplicate the noise and I was present the second time they started the motor. I showed both service writers the video that they were in agreement that something is wrong. If they're able to duplicate the noise, they can submit paperwork to replace engine.
Wouldn't you know it, started the car this morning before work, and the knock was present!
Maybe they put two bottles of STP Treatment in it, to quiet it down, prior to your arrival for the 2nd time.
I'm not sure if the end of my reply requires a joke - a smilie - or a frownie attached.....
I do know this! We cannot trust anyone these days, including a priest.