Instead of putting:
gamescope [arguments] in the wrapper section, instead you would do:
/usr/lib/extensions/vulkan/gamescope/bin/gamescope [arguments].
You just need the gamescope vulkan layer installed on flatpak.
Might also work with other launchers, but i dont know cause i havent tested.
Just thought id share this with anyone else who had this problem like i did.
its not a floating vest, its a invisible alien wearing a vest. smh my head