I can assure you this is fake. Notice how they use the same stock renders throughout the whole video. And yea, I know, they showed gameplay at the end. Wanna know how? Well I'm sure you all know they have the Gold Deagle from CoD4 in MW2. So they just did the opposite with the MP5K and SPAS-12. I love how on maps like overgrown they didn't even bother to shoop in the pictures of the gun. There was also the host ended game. Believe me, brix will be shat if any of these are true, but right now judging by shitty quality, they are fake.
1. The reason that the Deagle from CoD4 is in Mw2 is because the developers put that in the game. I'm pretty sure that they didn't actually edit the game itself to get that. And if that's true, then I'm sure they wouldn't have put the SPAS or MP5K in CoD4
2. The pictures that they "didn't shoop in the pictures of the gun" were most likely pictures taken in spectator mode or xploder, to show a view of the overall map, making it easier to see the landscape
3. The host ended game part was most likely because it was in a private match or splitscreen. I highly doubt any more than a few people have this, which would make it impossible to find a game in matchmaking that had this playlist