In need of advice/help on how to model a piece of upholstered furniture


First of all, please excuse my English.

I have been knocking my head around for the last week trying to come up with a solution for this problem.
I need to model this bed headrest (is that what it’s called?):

Of course (!) I need to use the least amount of polygons possible since it will be included in a real-time environment created inside a game engine (Unity). I would be modeling the piece in 3DSMax (2018).

I have no idea how to even start modeling this and make it look at LEAST reasonably “real”; I am aware of sculpting techniques, but I have no experience with that and I don’t have access to ZBrush (I do have access to MudBox, but I have tried to work with it and it seems limited). I installed and tried to do this using Marvelous Designer but I have not been that successful with that package either.

Believe me when I say that I have scrounged the Internet looking for any tutorial/guide/example for anything similar, to no avail.

Any, and I mean ANY help is most welcome. I am not a total noob regarding 3D modeling, but this one has beaten me to a pulp, so thanks in advance to anyone that shines some light on the subject, and if you can (please!) try and explain your suggestion as if I WERE a total noob, that would be even better.