Help! Wiped cam lobes? - Video inside

So I went to install the timing chain after work today and noticed that the little notch on the camshaft that mates up to the timing gear is not there. Its a groove instead of a raised piece of metal. It almost looks like it was supposed to be pressed in at the factory but never was? There's no way I'm supposed to have put it in is there? Is this a manufacturing defect?