On this page there are 2 different angles of the hit.
http://nfl.si.com/2014/01/19/aqib-talib-injury-new-england-patriots-wes-welker/
What is very telling is to watch the heads of the 2 bronco’s crossing in the lower frame. Neither were looking for the ball, and that is why it wasn’t caught. Today the receiver is being told to watch the ball and trust wes to take out the dback. ‘take out’ - I dont mean injure, I just mean remove from the play.
Disclaimer. I used to be a Pats fan. I wear a pats coat daily, but it is 20ish years old. I all-but-quit watching the NFL 13+ (or so) years ago when I thought it became to much like pro wrestling. So I never got to enjoy the 3 pats superbowl wins during those years. The pick play was one of the big reasons I quit watching.
I’m a Cincinnati native and have no dog in this fight. The upper video of the two you’ve linked clearly shows that Welker hit Aqib on his right shoulder/side and not on his left. He and whoever were running a crossing route, and the idea is to set a “moving pick” on the defense.
I remember in the Collinsworth era in Cincy that we were regularly called for pick plays. I don’t know how they determine the difference between a crossing route and a moving pick. Back then, I’m pretty sure they didn’t have collisions being part of the design.
In any case, you can make a case for Welker trying go under (Aqib’s right side) Aqib and not into him. My guess is that Welker as a long time vet knows not to just blatantly take out a defender.
I’ll be surprised if there’s a fine. I don’t see how you can prove it.