Do not agree w your interpretation of UE#3
yes Knox comes open but Allen is reading L modified Bow concept w Diggs option underneath and Davis on the deeper basic
by the time Allen around Brown to R side of field it's scramble drill and I think Knox is mad at himself for not coming back to QB and drifting into Davis
I think the error here is likely not hitting Kincaid immediately after you break contain, but this is splitting hairs here calling it an unforced error instead of just a normal play imo