I saw someone post that same thing on sherdog, and it was soundly refuted.
Diaz was promising to donate his purse to charity.
That's his business, not the promoters.
And as far as the weight change went, it was going to be 5 pounds over what was first discussed, but he came in the original weight at 180.
Estima came in at the original weight, Diaz didn't even show.