As demo we are playing with felguard not because hes dps is better. He give as more spell power our pack is stronger and we do overall more dmg with it because of that. If that is retail video we can see that warlock`s pet there hits average about 2.2 - 2.5k and crit over 5k
Here is a video from yesterday where you can see that my pet normal hits are in range 1.1 - 1.5k and crits a bit over 3k. When i`m in Demo form pets dmg looks like the normal dmg from your video.Keep in mind that my warlock is close to BIS and this one from your video is not at least the weapon is not. All the pets seems that are not doing the dmg they have to do. Lets hope that they will fix it soon, since they did great job on WOTLK expansion this year .
https://www.youtube.com/watch?v=Tw0ey-7eIHU