ECUs defective by water? 7.000,-€?

Hello together, Since my Phaeton has been standing under a tree according to VW due to the clogged processes on the windshield the engine control unit failed. Price something with 1.600,-€ After the test drive you find now, that also the gear control unit besides mechatronics still has to be replaced. (here the dealer directly asked VW, therefore according to error protocol also came this statement) Cost without installation 2.600,- besides also a regulator on the turbo some adjustment motor and already I am incl. installation at 7,000,- Kulanz at bj. 2006 and 125 TKM (3l TDI) nit. Can this all be? Any tips what I can still do (gear control unit can probably not be repaired, I already have telephoned) Just so swallow and pay, or still other possibilities? Best Grusss Achim