I have been trying to fix my Lexus is 350 for a while now, it has smart box issues anytime I put in a new smart box it gets damaged, pls help

 

Could it be water damage? Does it fail instantly? As far as I can tell the sunroof drain is right over it, or clipped close bye.

See video below. I hope this gentleman doesn't delete this video. It shows where the boxes are located. Lately these have been an issue for some.