A.M.
Place on the floor some clean, folded, natural fiber blankets covered by a sheet - safety pin or tape it in place underneath where the baby can't reach (even by accident) to hold it tight, and the baby will adapt. That should be enough padding.
Babies can sleep anywhere. There is always some fussing with any changes. Don't worry about it. If you've checked - no fever, no chill, not wet, not dirty, breathing well and normally - just croon a bit and pat your dear son, and go on to sleep.
Or you can always put your twin mattress on the floor, two secured blanket or quilt rolls for the baby (one on each side) and pad the floor for your hubby! It's just for a short time, and even if it's a few weeks or months, the floor will be good for his back!