If he has that amount of btc, he can easily provide proofs but I doubt he has that kind of money.
Maybe, he is using reverse psychology here or some sort of manipulation.
At first, he's angry at PD and now claiming to won such big amount. So he has basically ill motives of doing this stunt.
No proofs that has been showed to the public so like what other people are saying, you should take note of the word he said that he's about to sell something that can lead others to be scammed.
3. I stick to the original statement that anyone winning 150 BTC would be busy spending them and would not spend time trying to sell a method/strategy.
I agree, if I'm the person who had won this amount with any casino that allowed me to withdraw that large amount of money. There's no way for me to talk and discuss about that amount, I'll even think of those things that I'll buy and enjoy with portion of it.