It's possible the rubber hose got disconnected at the sunroof. You can lower gently the headliner on that side and take a peak. You will need to remove a few things that hold it in place.

For me when water was in glove box the rubber hose got kinked and it overflowed in the sunroof cassette from the sunroof -> down a pilar-> glove box and LCM but if it disconnects i would assume the water would take the same/similar path.

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2004 x5 3.0i AT.