Alright, here's the dealio on the skinny-fat body type with regard to abs.
Basically, you've got a high percentage of bodyfat even though your overall weight is low. That means you've got a lot of fat, and not a lot of muscle.
SO, what that means is that you've got a nice layer cake of fat over your belly. (Most likely, I'm not actually looking at your belly). Having a flat belly and having "a six pack" are basically the same thing. The only difference is that a flat belly means you've got a really thin layer of fat over your abs, and a six pack means you have no fat over them.
Getting to my point-- the only way to decrease the amount of fat over your abdominal area is to lose fat everywhere. There is no such thing as spot reducing. Now, keep in mind I didn't say "lose weight" I said "lose fat." So, theoretically, you could decrease your amount of bodyfat by working out in general, and also gain muscle in the process. This would either increase or maintain your weight. You would have to figure out approximately how many calories you burn in a day. (Try this link: http://tdeecalculator.net/) then eat that many calories or more if you don't want to lose weight.
Tl;dr Either of those videos are going to work your abs but you're still not going to have a flat stomach if that's the only thing you do all day.
