Hard to find anything about Coumadin (Warfarin) and MAOI's specifically.. But I did come across this about Coumadin:
"Pharmacokinetic mechanisms for drug interactions with COUMADIN are mainly enzyme induction, enzyme inhibition, and reduced plasma protein binding."
So certain types of enzyme inhibition can cause interactions with it. So I'm sorry I can't find anything more specific right now, but I think what I did find warrants some more research before you take anything with an MAOI.
I couldn't find anything about possible interactions with DMT however.
Stay safe!!
Embrace this moment, remember: We are eternal. All this pain is an illusion.