If its a company car= business lease?? then any other option other than bona -fide new parts for repair would not be an option. That said:- While the main problem was probably hydraulic lock as Pontoneer has said, with flood damaged cars the full cost of repairs can never be determined till engine strip down, rebuild and test as its impossible to determine what other parts have been damaged Ecu's turbo egr catalytic converter DPF gearbox controls etc etc. With todays electronic laden cars getting immersed in water is almost always terminal as far as insurance companies are concerned as its impossible to quantify the cost of repair till its finished- even then the car may never be the same as all those electrical connections have now been compromised with moisture ingress---- its a write off!