I’d break down that final set of plays as such.
1st & 10 - run the ball and get to the two minute warning. Failure to accomplish much.
2nd & 9 - the play was likely Shakir is the go route, although unlikely, if he gets open throw to him. Diggs is your underneath target if Shakir is covered. Shakir was open and thus Allen went for the TD.
3rd & 9 - Allen likely rebels or the plan was to roll out right. In my honest opinion, I think Allen knew McD had no intention of going for it on 4th down and was purely looking for a few more yards and let his defense pull off a miracle. However Allen has been burned by this too many times and effectively decided it was 1st down or nothing. He had no intention of making a risky triple coverage pass but hoped rolling out might cause the D to break a bit and allow him to either run or pass to the chains. Kinkaid was the open man but was short of the sticks with little chance of reaching the 1st since he was surrounded and his back was to the 1st. He however had faith Bass could kick it from 44. It wasn’t like we were at a 52 yd kick distance and thus need some extra yardage regardless. When it didn’t work he tossed out of play to assure the FG seemingly. Having to at least assume he’d get to pray the D pulled it off.
Personally I would of ran Allen on 1st down, then used 2nd down for something underneath, I wouldn’t have guys going to the end zone unless KC goes pure man which potentially would open up run options for Allen again. Then depending on that result you’d either pick up an easier 1st or be in prime real estate for a win or tie.