Propylene glycol is soluble in diethyl ether. In assuming you are speaking about an amphetamine or cocaine salt, most will be slightly soluble at best in ether.
Yes, it matters! When the hydrochloride is dissolved in propylenegylcole ( as you describe it) I see no real chance to precipitate the hydrochloride. The base will quite surely also be soluble in the glycole. The only thing you could try is to add a specific anion that forms a poorly soluble salt with your amine. So it matters what substance you have. Make a research concerning your compound and the properties of different salts.
But best would surely be a distillation under reduced pressure to get rid of the glycole.
Good luck
Neutralize it with alcoholic NaOH to form the freebase & NaCl, which will precipitate out. After removing the NaCl, add enough sulphuric acid in alcohol to neutraizr the freebase present. Sulphate salts of alkaloidal type compounds are generally nigh on insoluble in organic solvenrs like alcohols, si the sulphate sakt should slowly precipitate out