Take that away and he still would have a higher INT percentage than Cam and would effectively average 2INT in what is basically a 1 game sample size. Likewise I could play the same game with Cam's stats and say "count his rushing TD's" and all of a sudden he's probably on pace to go about 20TD's and 12INT's as the lowest volume passer in the league.
Cam is not bad in INT's this year either. He's a little lower than middle of the pack. 2/3rds of the league has 8 or more. Cam has 10. You can easily find an INT or 2 this year that wasn't Cam's fault and make him look pretty good in INT's if you play it that way.
Everything is percentage based and across the board we are just getting low volume. Cam has less pass attempts than his peers. It makes every pass alot more valuable. If a receiver doesn't get openened or drops an easy pass, it's more crucial, if Cam throws a pass into the dirt or it gets blocked, it's more of a miss because he just isn't having as many opportunities to make up for it. When you get to the redzone he's more likely to run it in or hand it off to get the TD because that volume is lower so naturally he has a lower passing TD percentage. INT's become more crucial again because it's on a precious few pass attempts, but if you are down in a game or are trying to get a drive that stalled out going you are going to take a low percentage throw anyways which is going to impact INT's
That's just on a statistical basis. Eye test what I see with Cam is a guy who has been coached to be ultra conservative this year who also lacks strong fundamental mechanics compounded by a spotty at best offensive line and a receiver corp that is not consistently getting seperation. On top of all that you have a lack of volume in passing opportunity