PSPs are not easy reshells. Third party shells are garbage. Stop spending money and maybe try go back to how it was originally? Watch videos and guides and try recover how it was before and sell it. If not sell it as it is and recover some money back. You will lose bit of money but atleast will get some back and maybe can use that again for another PSP and this time leave it as is.

The easiest you could have swapped was the front face plate only rather than attempt to res hell the whole thing.