It's a backwards in time extension of 'progressive revelation' and makes no sense whatsoever to anyone except Baha'is. Christians, atheists, secular people, all the Hindus of course, everyone claims that Hinduism has no known founder. You could look up 10 000 sources and that's what they would say. But if you looked up what Baha'is say, they say that Krishna is the founder of Hinduism. (I personally don't believe in Krishna as I'm in another sect.)
FYI, this was the original reason I got into a discussion with members of the Baha'i faith here on this forum ... just to point out that they were wrong about this ... even in polite terms, wishing for them to be more accurate ... for their sake. But as you can see from LofH's post, my discussion has had no effect whatsoever. That has to do with not listening to what people have to say. It's 'oh yeah, I understand', but then continue with the same old misconception as if nothing happened. Yes, it's annoying, yes it;s frustrating.
Good luck. I'll be out most likely. No point hitting my head against a brick wall for much longer ... again (sigh)