Coolant is puddling on the passenger side floor and the windshield fogs up.
I went through some deep puddles where water washed over the car during
major rain storms. Could I have torn off a heater line?
If a heater line broke you would have lost all your coolant rapidly. You more likely have a leaking heater core. A pressure test can be done via the heater hoses and tell you if it's leaking or not. Check a repair manual or on a Jeep forum for recommendations on how to replace. Some vehicles it requires removing the dash, on others you might be able to access it via the firewall.
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