Actually, if you read the paper, they looked hard for typical SARS CoV 2 lung injury and didn’t find it. He had ischemic bowel and died of sepsis and bacterial lung infection.
He was clearly viremic. What role if any that played in his demise is unclear.
Antibody dependent enhancement in dengue causes typical hemorrhagic fever. This is a very interesting case, it’s important to keep looking for ADE and to keep an open mind - but that’s probably not what this case was.
It may turn out that the choice of mRNA for spike, although easy to understand (and technologically spectacular) does not evoke the correct target.
If he was viremic without symptoms it was either very early infection or possibly the incomplete vaccination was giving some
protection. that he did not have typical findings…. I’m guessing early infection in host overwhelmed by already fatal sepsis.