IMO if it is not an authorized  repairable unit in your geographic area qualifiing for Total Care updateand repair, it doesn't pay to fix the damaged unit yourself, since the back up software out of update period likely will not work again after doing a factory reset to the device and the list price of the update is almost half what a new discounted unit will cost you that would have a warranty and two years of updates. If it were mine I would cut my losses, and just part it out, and sell off the remaining good parts on Ebay.