I would remove the catfaced tomato, but then I market 99% of tomatoes I grow and such tomatoes are not good sellers. Watering was not the issue here but likely cooler temps during flowering. You can opt to allow that fruit to ripen for home use, or you could pick for green tomato use. No harm done to those healthy looking plants either way.

I would def keep it Nothing wrong with it. You can just kind'a core the cracked part and use the rest.

Definitely keep it on the vine to ripen! That's a lovely tomato. You aren't selling it at a Franchise grocery store... these are homegrown tomatoes, grown for taste... not necessarily for looks. Cut that part off, and eat the rest.