The reason I'm asking, is because although the "I decided upon him" sounds fine, the "I decided him" sounds strange.

And the {wuq} is given as "decide, decide upon".

When you get multiple glosses in an entry, they're there to better guide you to the meaning and usage of the word. You don't have to be able to make the possible Klingon objects fit with every English term given.

The word wuq was used in Skybox S25 in the sentence ngoch luchermeH 'ej wo' San luwuqmeH pa' ghom tlhIngan yejquv DevwI'pu' [There] the leaders of the Klingon High Council meet to determine policy and decide upon the fate of the Empire. It was also used in KGT with DaH yIwuq Decide now!

Given the S25 sentence, I don't see any reason you can't wuq a person as well as you can wuq a fate. vIwuqpu' I decided upon him/her/it/them should be fine. The fact that you can decide fate but not decide him in English is just a quirk of English.

-- 
SuStel
http://trimboli.name