it could very well be that the solenoid that locks and unlocks your shift lever got wet in the water. when you press on your brake pedal, do you hear/feel a click in the shift lever? You should because this is the solenoid activating. The solenoid is activated by the brake light switch when you press down on the brake pedal. Do your brake lights work correctly because this is one way to test your brake light switch.
I would NOT try to disable your park lever lock mechanism. It is there for SAFETY!! So that the car does not run over you or someone else until you intentionally put your foot on the brake and shift OUT of park. Did you hear about the Audis that were running people over and killing people about 10 years ago. They had a problem with their PARK SHIFT LOCK!! I REALLY suggest that you do NOT go there.
Check the Brake Light Switch, as it will malfunction,and not let the shift interlock safety feature operate, You can sometimes check to see if your brake lights are operating, if they don't work or if they are on constantly, the switch is the culprit.