Help! Can't figure out 3rd bed!

I am currently on the Scarlett Lady and I'm having the worst night of sleep of my life! I'm the third in an XL Sea Terrace so I'm sleeping on the third bed (ground level, next to the regular bed), and I'm using the term bed liberally here. This is the most uncomfortable thing I've ever tried to sleep on, so I feel like I'm missing something! The cabin had those 2 square cushion things, which I put next to each other, and put the sheets on top of that. But this is such a hard surface! Am I missing a mattress somewhere? When I compare this to the actual bed, the bed is so much softer!

I'm quite worried I won't get a wink of sleep this entire journey! Thanks in advance for the help!