Problem:
So when I try to go fullscreen it only shows the top left part of the screen. I have tried this with numerous resolutions, both higher and lower than my native. I have tried changing my native resolution as well. All that happens is that the game gets lower quality.

Drivers are as updated as can be.

Running windows 10 through bootcamp on a 13" Macbook pro (mid '14)

this happened to me as well and the first way is to go to compability and check disable display scaling on high dpi settings or if it did not work you need to reinstall it ;)

type this:
/re width height

replace width & height with the values of your resolution