I was wondering if I was going to break other Windows devs, since no one else had reported having an issue with the linker.

In FindSDL2.cmake, I added that variable (SDL2_LIBRARY_PATH), and set SDL2_LIBRARY_ONLY equal to it. I'm no expert on CMake, but what are the values set to in the cache (in your build directory, it should be called CMakeCache.txt)?

It seems that I also made a typo, and made SDL2_LIBRARY_ONLY a string, not a FILEPATH.