Hello SKA, did you ever try this? If yes, What happened? Thank you.

benzyme mentioned that the central position may not be affected in post #45:

I think this applies to 5-position substituted tryptamines. If so, this means 4-OH may not attach due to the 5-MeO interfering with the psiH enzyme (today we know the enzymatic pathways thanks to the paper published in 2017).

So with melatonin in the substrate this may happen:

Melatonin-> 5-MeO-MT + CO2 (this is catalized by the enzyme psiD and could be a rate limiting step)

5-MeO-MT + 2 SAMe -> 5-MeO-DMT + 2 SAH (catalized by psiM)

So you could get 5-MeO-DMT as inmotion mentioned earlier in this thread. Once upon a time shulgin said you could get  4,5-HO-MeO-DMT (see Ask Dr. Shulgin Online: 4-Hydroxy-5-methoxy-N,N-dimethyltryptamine, Psilocybe mushrooms, Psilocin )

Either way you would probably get something interesting by feeding mushrooms melatonin.

PS: Thanks to werd for pointing me to this interesting thread