A black hole, as I understand it, relates to the density of the matter and energy that forms it, not the total mass. Total mass is a really good way to create one, but not the only way.
If you compress the particles of a few collided atoms into one little micro-blackhole like he is talking about, it's mass shouldn't be more than mass that went into it. It's just very dense.
This has to do with space-time curvature, and I was terrible at that level of physics in college. I am a computer science guy. I can only relate what I remember from many moons ago. You need to learn tensors and then you can define fields that warp or something like that. A black hole relates to curvature, not directly to mass.