Actually, it pains me to disagree with Dale as he's usually correct in his notion/opinion/expertise that WC and BJJ have nothing to do with each other, but a Lop Sau, by definition, means controlling hand. Pulling is implied, but theres nothing incorrect with an inside lop sau/dar. There doesn't need to be a pull in any one direction. Its a distinction between resting your hand on an opponent (Fook Sau) and grabbing it.
I will, however, state that an "arm drag", as show in the second vid, is not a WC technique as it does not follow any of the (in general with respect to various WC lineages etc.) principles, theories of WC. The initial grab on the inside of the wrist to set up the arm drag is an inside lop sau, but nothing after that even remotely.