I think there are two problems:
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The residual antifreeze odor from the original leak, and
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the new, stronger smell and possible loss of coolant.
Theory for 1): You say “I had a wet carpet,” which means the antifreeze dripped onto the carpet. Antifreeze takes a LONG time to evaporate, which means you’ll smell it for a while. In addition, the padding under the carpet may have soaked up some of the leaking antifreeze. This padding is a sponge-like material, which will hold any liquid (water, antifreeze, beer) like, for lack of a better term, a sponge.
The only way to dry the padding (if it’s wet) is to get it out from under the carpet (easier said than done) and allow it to dry outside. If you find your under-carpet padding soaked with antifreeze I suggest hosing it off really well, with clean water, before letting it dry.
The fact that you have no more fogging is a good sign. Maybe the antifreeze is just in the carpet, and not the padding. If this were my car I’d want to check the padding, just to be sure.
Questions for 2): When you smelled this new, stronger smell, was it the first time you used the heat/blower since the heater core replacement? Do you have the car now, or is it still in the shop?