I think, and I mean this kindly OP, that you need to let this go. A horrible tragedy occurred when a unique set of circumstances combined in an unforeseeable way to lead to this baby's death. Pretty much everything can be dangerous in the wrong combination of circumstances.
Someone I know on FB recently shared a picture of a baby's foot where the baby nearly lost a toe after a loose thread on one of the socks got tangled around the baby's toe and caused the blood supply to cut off. This is not the same thing as saying that socks are dangerous. It is to illustrate the point that everything is potentially dangerous, even things as seemingly banal as socks. And you cannot similarly have expected the manufacturer of the socks to have foreseen that this was going to happen. It is the same with the bednest. You cannot possibly make everything completely risk free or foresee every possible risk or eventuality.
I'm sure if NCT / bednest would have been able to see into the future they would have done everything possible to make the product safer (not that I feel the product was directly at fault, as I say it was a unique combination of circumstances). If nothing else from their business interests alone any company manufacturing products for children would want them to be as safe as possible to avoid negative publicity.
So I reiterate again, in all kindness, please let it go, for the sake of your health and sanity.
And no before you say it, I am not a member of, nor work for, NCT.