Great topic - lots to respond to. The concept of a decision tree might work with a few players but not a lot. Wallner doesn’t even know the dead ball rule and he is going to effectively judge when game strategy calls for a challenge - don’t think so. Jeffers is really adept at it making his usage far more important than a hitter. I would treat it like stealing a base for the hitters. If you haven’t been given the green light you don’t challenge. That way the manager can decide who and when are the right times to challenge. From a game theory perspective there is almost no time a hitter should challenge at the beginning of the game.
Lastly, each club keeps track of umpire tendencies so the catchers can really go to school on where the ump is likely to miss. Likewise, clever pitchers and catchers will note where a hitter has incorrectly challenged a call as it is a sure tell of a hole in the batter’s judgment. Not to pick on Wallner but I believe all his bad challenges have been on balls up in the zone.