What does it mean he had to sign "to get paid"?
They have to pay him for the fights he takes under his existing contract; that can't be contingent on him signing an extension. If he's saying he had to sign an extension to get more money for the fights he already had in his contract, then duh. What does he expect the UFC to do?
"Here, have more money for the remaining fights for your current contract, and we don't ask you to stay with the company for any longer so if your value continues to rise you can fly away to the competition!"
That would be a moronic investment. If he feels the UFC is unfair in its business practices and didn't pay enough, then don't sign the extension, finish your contract, and go somewhere you think you can be better appreciated/paid.
The UFC is not going to renegotiate after every fight, and they're not going overspend on essentially a journeyman who they know is one or two fights away from being back in he sidelines. He is riding a wave because of his streak, but if he loses once or twice in a row his stock will greatly diminish. And he very well might.
Also, how about posting his actual contract and telling people what he actually makes?