[charlesdm]

How could he even prove that?

Why would an investor, who has potentially invested money in this venture, hand over evidence like that?

I'd assume they'd just attribute him in the future (in some obscure corner of their product/website), and be done with it.

[task_queue]

An investor associated with that venture went out of his way to spill the beans and probably would hand it over unknowingly if asked nicely.

But I agree with your conclusion.