He was in a trench during a siege. I would say the likelihood he was killed by a stray musket or grapeshot are way way way above a stray meteor. And you must always go for the most logical answer.

At this time of year, at this time of day, in this part of the country, localized entirely within your kitchen?

Since the projectile which killed him penetrated the left side of his skull and exited the right side in a horizontal line, he would have had to have been lying down if it was a meteorite coming from above, and none of the witness accounts support this.