The loss of delayed lights and interior lights/door issues point to the ‘Brain’ or what is actually called the ‘CLP/SSM module in the trunk. Water has damaged it severely and it is no longer operating properly. The delayed lights both interior and exterior are timed by it.
That is my opinion anyway, damaged plugs means the water was quite high and got inside the module.
If you buy a used module make darn sure you get the four plugs with pigtails as you cannot rely on your plugs to be trouble free because of the corrosion that is possibly on them.