Well your answer would be in my knowledge i have never heard of anyone  using the 3 without the digoxin , to be honest this DDMA is used legally by legislative bodies to carry out end of life treatment, it is not something the common person would find easy to get hold of the required medicine in the required amounts . Personally if i was able to get the Morphine and Valium and Amitriptyline of the required amounts and i really really wanted to CTB after careful and exhaustive thought process , i would either over order the generic Indian dose of tablets hoping i would catch up the lack of purity or if i had money travel to certain countries where genuine Digoxin could be purchased possibly over the counter .. my thoughts worth on your question