I think you have an incorrect death date for Henry. He couldn't have livedin Washington Co. IN because it wasn't created until 1813.
I'd look for his death info in Maryland since you know he died there. If you don't know where he died in Maryland, post your query on the Maryland, Unknown Message Board.
When you get this far back in time, Ancestry and FamilySearch has little. You need to look for books and what's in the person's probate records, tax and deed records. Successful Searching & Happy Holidays!