Is this a quote, a Latin phrase, etc? It reminds me of "Who benefits" and 'Who watches the watchmen".
Kiu used without a noun refers to a person. If you have a noun after kiu, it means which. Kiu hundo decidos, that means "which dog will decide". "what will decide" is kio decidos.
La jugxistoj decidos La similulo al mi atendi Estas simpla kaj estas neluksa Kial mi devos pleni?
Is this pronunciation of "decidos" in the realm of mainstream EO? In the very first "Tips and Notes" of Basics the "o" is pronounced like "oh" in English. To my ear, the pronunciation of decidos was close to "decidas" or more like the "awe" in "awesome" or the "DOS" in the old "MS-DOS."