You asked about Ransom Dudley Blades and his son Isaac Till(gh)man b: 1847 Greene Co., MO. To my knowledge this family line originated from MD - ours, if Luke is the progenitor, were from SC. I don't know of any relationship at this time.
The only known excursion to my knowledge into MO by our family was a son of my Isaac's (William S.(Smith?) Blades)during Civil War (see below). I can trace my Isaac via census and marriage records from 1840 through 1870 with the single exception of 1860 (again see below) - in 1860 both Isaac Blades and his son-in-law Erasmus Sweet have not yet been located.
1840 IN Bartholomew Co., Liberty Twp. - census
1850 IN Howard Co., Taylor Twp. - census
1852/1853 IA, Story Co., Lafayette twp. Isaac and Sarah (Smith) Blades remove to Story Co. Iowa
1856 IA Story Co., Lafayette Twp. - census
1860 Isaac Blades and Erasmus D. Sweet families both missing from census so far
1862 – 1863 - Isaac and Sarah’s son William S. Blades enlisted Sept. 6, 1862 13th Kansas infantry Co. G – he died Feb. 6, 1863 @ Springfield Mo. Mother Sarah filed for benefits in Colorado.
1870 KS, Marshall Co., Vermillion Twp. – militia- census
after this Isaac and Sarah Smith Blades disappear. Their son-in-law and daughter Erasmus and Elizabeth Blades Sweet move approx. 1877/78 via NV and Dalles OR, to Freeman, Spokane Co. WA by 1880.