hey i figured it out! my dumbass forgot to add the @tool keyword at the top of the panel script that’s why it won’t work
Thanks to gertkeno’s help i found a solution
Leaving this for anyone who comes across this issue in the future: if you want your UI scene to display properly in the main Panel you must make sure you UI scene size_flags_vertical is set to Control.SIZE_FIll_EXPAND
Also make sure to have @tool keyword on top of each script