Yes, though the problem has been solved!
My dev partner reminded me: “Aren’t we using 2FA with zoho?”
Yes, yes we were, but I only had it on for specific users - what I did NOT know was that if eve one user has it activated, the umbrella system won’t let any other user log in without turning on 2FA as well – so going into noreply’s account and creating a specific application password for discourse solved that issue.
Sorry for wasted topic, but hopefully this will help any other user who may have a similar system.