I’ve been searching a database of deaths in Illinois in the mid-20th century. While searching this database, I have to constantly remind myself of where people in “my county” were likely to die if they did not die in “my county.” The two most likely places were nearby hospitals and state institutions. In my case, most out of county hospital deaths took place in one of three nearby cities. Those cities were located in different counties.
A significant number of deaths took place in a state institution eighty miles a way which was located in a county that was not adjacent to the county of interest.
In addition to institutions it is always possible that your relative died in the hospital, nursing home, or institution that was near a close relative and quite a distance away from the “home location.”