Welcome to this AutoHotkey forum!
If you believe that the color is present, check it as follows.
1.
MouseMove to the coordinate to verify it.
2. Use
PixelGetColor, and display the color at that location.
Try without full screen as well.
Some games block scripting.
You do not need to wait, in a loop, for a key to be pressed each time. This is the purpose of a hotkey.
Your current script requires very precise timing between the key press and when the pixel is found. This is not necessary, and it decreases the chances of success. Instead, you can have a loop that repeatedly searches for your target color
after your special key is pressed. When the search succeeds, your button can be activated. Many forum scripts-- hundreds or thousands-- have been posted that accomplish this task.