Walking the batter puts another runner in scoring position.And you HAVE TO WIN. What do you do?
Conventional wisdom for other team is sacrifice bunt. My first instinct is put the batter on to load the bases, but you're giving them an extra out by doing that.
"Play good defense" is a disqualifying response.
1) Are you so sure your team can come back from 2 runs, or are you more apt to overcome 1 run down?
2) Nothing guarantees the runner at 3rd WILL score, but it is likely. A low-ball pitcher with average skills is more likely to throw a wild pitch, but also more likely to get a ground ball.
3) If my pitcher/catcher are well trained, it is a good time for a pitch-out to see what the opposition is thinking and potentially catching the runner off 3rd.
4) Do you allow the runner on 1st to waltz into 2nd base? Which runner is your real priority?
5) If the batter squares to bunt, is the bat presented low? If so don't waste pitches too far out of the strike-zone, let her pop up a pitch in the upper zone.
6) Normally with a runner on 1st, late innings, you would play "waffle-defense", guarding against the extra base hit. Corners half s step closer to the line, outfield back 5 steps. Your runner priority will dictate this. Do you play normal, against the extra-base hit, or for example play back only CF and LF?
7) Who do you have coming up? I would prefer girls who can create runs and pressure personally.