Searched around for about 30 minutes and couldn't find the answer I was looking for. It's probably right in front of me, but I'm missing it if it is.

Swim did 6 pulls into separate jars and put it in his ice-cold freezer a litle more than a week ago. He's been out of town since, but when he checked the morning before leaving there had been a very nice collection of crystals. Is his batch still "good", being that the jars have been left untouched since leaving, or can one freeze precip for TOO long?

I'm not so expert, but i think is not harmful, naphta don't freeze and the crystal have time to precipitate.

Your crystals will be fine! Precipitated crystals are pretty stable especially when kept in cold temperatures.