It's possible they may have seen those, but here's a possibility too...THEY WERE BUSY MAKING MOVIES!
My goodness! Do you guys really want to bitch and complain about what songs they used and how they constantly are just trying to steal "ams" songs? Yes, it's possible they saw an edit and were like "whoa, that's a good song. let's license it". However you have to realize something, they aren't on NS all the effing time watching edits. They are filming! Traveling! Getting way too drunk to remember what edit they heard what song in!
Here is what a bunch of you guys should do. Write to a film company and say you want to be a music research intern. That way you can get paid for watching all the edits you can, taking notes of what music was used. Because if you're not getting paid to watch all those edits, maybe you should find a way to get paid. Otherwise you're probably just gonna bitch in thread like this while FILM MAKERS are out making movies and NOT watching edits in their parents' house.