Ah that sometimes happens. The issue is that they are all at positioned at the same exact point in UV space, so scaling them won't really work since Blender doesn't know in what direction to scale them outwards.
What I would try doing is select those two triangles like you have in the video, and re-unwrap just those. Then you can resize them using the texel density that you have set for the rest of your model. Hopefully once that's accomplished, you shouldn't be getting any more of those baking errors!
