w124 wagon third row seat water leak

[87tdwagen]

Hello all,

After some driving in intense rain I have found that the third row seat footwell area was quite damp, I show no signs of leakage around my tailgate or rear windows. I checked inside the two side panels and all was dry in there.

Any ideas how this water is entering the footwell from below? I cannot find any obvious signs of entry.

Thanks,