This is the USA, you're right, there was probably no one in the office at that time!
Still does not satisfy the very basic question of why it ended up in his email when in reality he is no longer involved at the company, and other than being a stock holder and having "friends" that work there, no longer has any management ties to Regentech.
You probably should have asked him why it was redirected to him. His statement of he gets lots of emails does not satisfy the question of why your email directed to Regentech ended up in his box.
That of course would have been one of my first questions, especially after he had told me he had been contacted by securities regulators limiting his release of information.
This whole redirected email path from Regentech to Dr. Rudd & his subsequent statements concern my somewhat analytical & exploratory mind.