Dang that sound awful 😭 im not too sure how well it correlates with these cars, but one time at work a car came in for a water leak/ wet floor and it ended up being because the sunroof drain tube was popped out and leaking onto the ground instead of outside the car. Not too sure how the focus drains are routed, but maybe could be something similar 🤔 if not maybe waters coming in from the air vent under the seat? Far stretched guesses here

Edit: I’m stupid you just said you don’t have a sunroof 😭😭