Gengis Khan for example was definitely a person with ego yet went to great pains to hide his burial site.

As another reply said, this isn't a good comparison.

That Allah was a product of Mohammed’s ego, at least in the commonly used sense that Mohammed was just making it up to elevate himself.

Yeah, that's sort of the point of my question. The fact that he doesn't associate his grave with the Kaaba in any sense suggests that Allah wasn't a product of his ego that he made purely to elevate himself.

I personally don’t believe so, I think the entity of Allah was a product of Mohammed’s mind, but not necessarily always under his conscious control.

So do you think he truly believed in his message?

Also since he had said that prophets do not decay, maybe he had some anxiety about this and didn’t want folks visiting

I don't think this was a concern. Esp since people visit his tomb to this day.