Lacking formal training does not equate cannot understand something. As far as copying something goes, there should have been an equivalent mathematician nearby from whom he can copy, right? Who is it?
As an atheist myself, I do not believe in god and I do not believe Ramanujam got it from god. However, it does not change the fact Ramanujan thought he got it from god because he could not necessarily explain how he made those intuitive leaps.
The results of his collaboration with Hardy (the approximations for the partition function and the circle method) make it clear he knew well what he was doing. Nobody was doing anything similar at the time.
A feline can make a precise jump between two points and be utterly unable to explain how it computed the force signals to send to its legs to make the jump. It probably doesn't even know force or muscles. Formal training isn't everything.
As an atheist myself, I do not believe in god and I do not believe Ramanujam got it from god. However, it does not change the fact Ramanujan thought he got it from god because he could not necessarily explain how he made those intuitive leaps.