McVay has consistently passed in that situation. I.e., needing one first down to ice the game. He is the anti-Fisher, even when conventional wisdom says run 3x and punt. McVay trusts his offense to get the first down and not give the ball back to the Chiefs.
Trying to get 15 yards running the ball against zero coverage is an extreme longshot. McVay characterized it as a tackling drill. Which meant conventional wisdom amounted to giving the Chiefs the ball back with about a minute fifteen seconds with no time outs needing only a field goal. This included a likely punt return by Hunt (Hill?), which could have put the Chiefs in field goal range alone if Hecker had not raked that ball like he did. McVay's strategy to end the game in victory formation, rather than with his defense trying to protect against Tyrek Hill getting behind the defense and at the same time protecting the sidelines and Kelsey running up the seam, and trying to keep KC out of field goal range, seems far more prudent than KC having one time out.
So McVay's strategy, due to a fluke tipped pass, meant that the risk for trying to win the game was an extra time out by KC. Could it have been critical? Possibly, but the defense still needed to stop KC whether they had zero time outs, one time out, or three time outs. As it turned out, the time out didn't even come into play.
I also think that Goff was instructed to slide if the passes weren't open to keep the clock running. And I submit that Higbee WAS open on the tipped pass, the safety just made a better play. It doens't mean it was the wrong call, and if you are upset about the play calling be prepared to be upset in the future. McVay will pass again in the same situation, count on it.