After reading
this thread, I've decided to try AHK once and for all. (Prior to this I was using non-copy pasted AHK scripts)
I don't know why I didn't try nomousy first but I pasted the script, didn't turn it into an .exe via compile script since I didn't see the option and now I have an invisible mouse cursor and it took me minutes just to type this since I don't know how to work by keyboard shortcuts and was relying on cues. (Luckily I was still logged in to this forum via Firefox)
I've tried re-clicking the .ahk script but it doesn't re-enable the mouse cursor.