lots of plants are made into tea, although most don't have a psychotropic effect. Seems entirely plausible that two separate teas were brewed and consumed which, in combination, caused quite a notable effect.
Also, you talk about naturally occuring DMT, but be aware that there is absolutely no scientific proof that DMT is contained in any amount sufficient to provoke a trip in the human body, even with a MAOI; it's there, yes, but in minute amounts and almost certainly as a byproduct of the synthesis of something else. Maybe you're right on the other hormones, but if that's the case it's not due to the MAOI properties of harmals either, since we're not seeing people using pharmaceutical MAOIs tripping.