This superinfection killed most of the victims, typically after a somewhat prolonged death bed.
The problem is see here is that during the second round of the pandemic, when the young and healthy were the hardest hit, many victims fell ill in the morning and died by the afternoon.
I also dont see how Boston could be the source of the outbreak if it begin there in August 1918 when the first case at Fort Riley in Kansas was in March of that year. Recent investigations have also pointed to a British army camp in Étaples, France as the possible source. Soldiers there experienced very similar symptoms I believe as far back as 1917.
It is a case of "typically " vs. "many."
I also dont see how Boston could be the source of the outbreak if it begin there in August 1918 when the first case at Fort Riley in Kansas was in March of that year.
That is one of many debatable postulations.