yeah it can be a sign of tryptamines.. maybe the acacia you extract from has much dmt n-oxide which is an oil that wont crystalize..
instead of straight away getting a different solvent, why dont you do as I said and search for an MSDS of the solvent you have to see if it has details on what are the exact contents of it? Also before getting a new solvent, read properly the labels and also search for the MSDS (google MSDS + name and brand of solvent, for example "MSDS merck naphtha" ), and see if its good one, dont just buy things randomly as it may be a waste of money.
By the way, you said 'its been in the freezer overnight'.. What has been in the freezer, the oil, or did you redissovle in naphtha before? and if your redissolved, was it a minimum amount of it? because if you put the oil in the freezer or if you redissolved in too much naphtha, it wont crystalize.. Have it dissolved in a very small amount of warm solvent, just enough to dissolve most of the goo, leaving some darker impurities behind. Then freeze.
in the last case, if you cant get it to crystalize, what you can do is, weigh a small amount of herbs, dissolve the goo in pure non-denatured acetone/IPA/alcohol, and let it evap onto the herbs.. After they are dry, weigh the herbs to find how much product you have.... and you can smoke these herbs.