High amounts of base tend to cause a lot of stuff to get pushed into the nonpolar layer. The same thing happens with naphtha. You could dilute the solution with water, and that would probably help.
You could also take the DMT-smelling gunk, dissolve it in vinegar, and reduce any DMT N-oxide to DMT acetate with zinc dust/powder. Then filter out the insolubles and the zinc, such as with a coffee filter. You could defat at this step, by adding some heptane, mixing thoroughly, and discarding that heptane, but I don't know if such a step is necessary. Whether or not you defatted, you can now add clean heptane, basify the solution up to about pH 13, and pull out your spice.
If you don't do the procedure in the above paragraph, you can still clean your gunk up by redissolving in heptane, washing with sodium carbonate solution, and freeze-precipping the heptane. Hopefully, it will give you snow white.