Suggestions for Honolulu dining gift certificate

A friend on the Mainland wants me to get a gift certificate for a restaurant to give to a businessman who has done my friend an important service but refused payment. Don't know the tastes of this businessman so am looking for suggestions that would be for nice, but maybe not fine dining, and that would allow for a range of options.

The business is located between Waikiki and Kahala; don't know where he lives, but would imagine any venue between downtown and Hawaii Kai might be ok. Gift certificate would probably be in the range of $100.

Suggestions?