That final out was dumb, did he really think that ball wouldn’t be caught?
Agreed.
That is a very common error for baserunners.
They have to make a split second judgement—and often get it wrong.
I think the runner was banking on being the tying run. I don’t know, had it not been the bottom of the ninth in the (potential) winning game of the World Series, he probably would have stayed closer to second. He got caught up in the moment. Still bad base running. Ended the game.