I ripped that first picture from the internet. I meant for it to make a basic point regarding "how" the rocker arm TIP sweeps across the end of the valve when the geometry is correct. But of course you're hung up on the point of contact being the axis of the roller tip …. which was not my point.
I should have dug-up this picture instead. This is another picture I created, this one is over a decade old, best I can remember. It was originally done to 1:1 scale.
