Despite a number of assumptions here that would have to be true first (like the development of AI in the first place)

A number of assumptions yes, but actually I see this is a viable route to creating AI, not something you do after you already have AI. Perhaps the biggest problem in AI right now is the grounding problem - actually truly learning what nouns and verbs mean. I think the most straightforward viable approach is simulation in virtual reality.

real concern would be how you manage such an expiriment without the whole world knowing about it, or with the whole world knowing about it but make it safe so some terrorists can't blow it up, hackers tamper with it, or spies steal it. The world's reaction to AI is my biggest concern in any AI development scenario.

I concur with your concern. However, I don't know if such an experiment necessarily must be kept a secret (although that certainly is an option, and if/when governments take this seriously, it may be so).

On the other hand, at the moment most of the world seems to be blissfully unconcerned with AI atm.