I posed this to my 7th graders this year. They decided the colonists attempted to move to the Coatoan, as the sign implied, but that the 50 mile distance was to dangerous on foot. The kids posed that the colonists attempted to build a vessel or vessels to take them the 50 miles and were lost in a storm. This would explain why no trace was discovered and why many articles were left behind. I thought it was a pretty good bit of reasoning for 12 year olds form working class Queens.
Wouldn't that be "too" dangerous?