KCI, R blocked into receiver

[Theisey]

I'm not going to get into a what if this or what if that battle.
I did not assume K was first to block R2. Seemed clear to me that it's R's job to block K so their receiver can get some running room.
The R players are 5 yards apart. That's far enough apart for me to assume that R2 had one thing in mind and that was to block K.
Unfortunately for R2, K was possibly bigger and faster and cleaned his clock so to speak thus causing R2 to collide with R1.

KCI on K? not in my opinion, nor do I see by any rule either.