I don't believe that you're correct in your code info on the rear folding bench seats. The code is 287 and I have double checked with the vin for my car and it is also 287.
Both mine (and my second E55K; I don't have the datacard for the first) had Option 287 - 'Through Loading Feature', but only one had option 844 - 'FOLDING BENCH SEAT IN CARGO AREA'. That was the seven-seater E500.
Sunroof? Oh, FFS. It has a sunroof; end of. It wouldn't have a panoramic roof; they were offered on the facelift 211 in the USA, but not I think on the pre-facelift anywhere.
It has pre-facelift headlights.
It has facelift mirrors, grille and presumably front bumper.
(The seller doesn't claim it's a facelift, so he's not trying to fool anybody).
It doesn't have seven seats; the seller doesn't claim it has, and the datacard posted doesn't have Option 844, so it's not supposed to have them.
There's nothing much amiss with the MoT history; it covered very few miles in 2019, during the main Covid outbreak, but so did my cars, because I wasn't going anywhere.
We don't know anything about the service history, apart from v-belts and pulleys, recent front suspension work and brake pads, and a new water pump. If the engine mounts haven't been changed from new, it will shake like a b*****d at idle, but I'd bet they have. If the Airmatic works, that's had maintenance too, and the same goes for the SBC.
I think it's a perfectly genuine, very high-spec E500 estate and there's probably not much wrong with it.