The fielding stats are very quirky on the lineup screen. I select fielding stats and all batters, and there are no fielding stats. I select all players, and the stats appear. I select a split (playoffs in this instance), and the stats don't change from the season totals. None of the month splits work, either. And now that I look at it, no splits work with fielding stats. What's up with that?
I wanted to see how many errors my 3B has made in the playoffs so far, because it's gotta be like 7 or 8 in 15 games (and he's rated a 9 out of 10 at 3B

).
This is the most up to date patch, Windows version, and I doubt the universe set up is relevant, other than I have high stats detail and keep all career fielding stats enabled.