Is there an emergency release to fold the rear seats down in a W205 estate?
As far as I can tell the only way to fold the rear seats down is with the switches in the rear on the right and left side of the boot as shown below.

I have a dog cage in the back with an emergency escape hatch in the rear. The idea being that if the rear end is crumpled in an accident and can't be opened, the dog can be removed from the other end. The only problem is as far as I can tell the only way to release the rear seats is from those switches with the tailgate open. Am I wrong? Is there another way of doing it?

There's a release next to the rear seats, one on each side of the vehicle. The 'switch' looks the same as the ones in the boot.

Huh, mine doesn't seem to have it. There are two plastic inserts either side that look like where a switch would go if one were installed, but for whatever reason mine doesn't appear to have them.

The interior switches only seem to have been on earlier models.

My previous 2017 premium had the switches inside, my current 2019 premium plus doesn't.

have you tried contacting Mercedes customer support ?

That'll be what it is then. Mine is a 2021 so obviously has no other way of folding the rear seats - seems a bit of an oversite to me. Wouldn't be so bad if they were in the boot/trunk but further in towards the front of the vehicle. The fact they are right where the door closes means you would be completey stuck if the rear malfunctions.