I think the other WR (#7) makes a better case for a call against ND, but the FSU player who got the PI call was holding the ND (#20) player. Not sure if those would offset or replay the down. Even on #7 though you can see it's the FSU who is jamming up into the path of 7.
Still wrong call IMO, and on clear review a very blatant wrong call.
But bottom line for me is that FSU blew the coverage and got bailed out by the refs.
I see the design of the play as either both #20 or #7 picking FSU #26, depending on whether goes over or under, or #7 picking FSU #26 and #20 picking FSU #8 on a switch. The one good thing FSU did on that play was play it tight, forcing ND to drive into the defenders. DBs are allowed contact within 5 yards. Problem is the the WRs are still driving when the ball is in the air. They should have had their hands in the air or acted like they were fighting through the contact. As it was, they drove the defenders into the end zone. Also, if Robinson went lateral without cross scrimmage it would have been legal.
It actually was the perfect offensive call. They just screwed up on the execution. Even if the receivers just go straight and into the end zone and avoid contact its gonna take the dbs with them. Even if FSU #8 was switching he wouldn't have been able to stop #88 unless he totally jumped the route. On this vine angle, you could even make the case that #20 was blocking FSU #8 when he tried to switch to #88.
https://vine.co/v/ObOBAdPbI5a/embed
The receivers can run their routes, but they cannot block downfield on a forward pass before the completion. When the ball is in the air, defensive players are eligible receivers too. Like I said, I could see a no call, but wouldn't argue with the call either. I think Kelly made a calculated decision when they designed this play that they could get away with it. If the coverage wasn't so tight they probably would have.