Can anyone please tell me what monkey meat tastes like specifically as I'm researching for a short story?

Depends on the type of monkey but its somewhere between pork and deer.

The texture is very close to pork with a soft meatiness that flakes apart slightly rather than crumbling (Fatty pork flakes apart, in contrast to say a dry over cooked beef or a ground beef which crumbles apart).

The taste can vary widely depending on the diet of the animal but typically has a slightly gamy flavor not unlike wild deer (though deer has a texture closer to beef, which a monkey does not)

The fattier parts of a monkey come close in texture and silkiness to duck breast (with the skin), but without the hint of fishiness that comes with water foul.

Im not sure how else to describe it, it is unique and does not just "taste like chicken".

If you really wanted to come close you could take a fresh thick cut pork chop, butterfly it and stuff it with ground deer meat, rap the entire thing in fatty duck skin and bake till the middle is medium. Dont let it dry out though you can crisp the outer skin if you like.

Basically your trying to recreate a fatty, oily meat that flakes apart with a bit of gamyness. Duck skin, pork texture, deer flavor. It wont be perfect but, sort of. And if your duck skin happens to be slightly fishy (some are), ignore that part in your description.