He sounds sincere.
His letter reminds me of a couple of times I came up with an idea that helped a certain company. They did everything in their power to make my intellect theirs for free.
Big companies think they can bring the little guy in close and then trample him or her. Sadly, they often DO.
This may be that case. There's a possibility that the big company only wants the little guy's idea and is telling him what he wants to hear, but doesn't want the public to see what they are really doing. THIS happens as much as CEOs of pink companies lying. Its a dog eat dog world on all levels.
All IMO
My job is so secret, I don't even know what it is.