Under Dash water leak
Well here go's nothing.
Put a water sprinkler under the car on the drivers side and let it hit the fire wall.
let it run for 15 to 20 min if it don't leak put a slow running water hose on the wind sheild on the drivers side and jack up the passenger side.
If it still don't leak then do the other side the same way.
Just thought I would give you my 10 cents worth
This is how we find water leaks in new car's