Factual error: 10-4 "The Friends of Joey Kalima": Guest star John Rubinstein (son of classical pianist Artur Rubinstein) guest stars as Joey - but his name is misspelled in the end credits as "Rubenstein."
Factual error: 10-13 "The Big Aloha": McGarrett compliments Palahana on his surfing skills with the line, "Nice ride." But the ocean behind them in the shot is virtually flat. With no waves, Palahana's supposed "nice ride" is impossible.
Answer: He was fired. He never really appreciated his character. He felt Kono was portrayed as a big dumb Hawaiian and that the stereotype was racist. He also felt underutilized. He was fired after a heated argument with the show's publicist regarding his character. It seems there's not much details given regarding the incident or the firing, so it's seems possible he upset the show's producers as well.
Bishop73
No he said something derogatory about one of the Jewish producers that's why he was fired.