Hey @Gpaw, I believe your wife is right about the creams , but if you use the roots the creams are more effective. 
It’s possible to infuse the roots into coconut oil.
I am almost sure that there are recipes in @ReikoX thread not just another tincture thread and @sebring has in its site some kind of cream.
I think he will like to read the topic, he is super rich in medical information, or at least he’ll give you an idea which better option, reikox, sebring and also @PSam understand a lot about medicinal creams and infusions including DSMO 
