For what it's worth, there is a brief bio of him in Brewer's History of Alabama.

"Robert T. Scott was for many years a citizen of this county. He was born in North Carolina about the year 1798, and came with his parents to Alabama in 1817. They settled in Madison, where Mr. Scott was a planter. In 1830 he represented Madison in the lower house, but soon after came to Jackson, and was here a hotel proprietor and farmer. In the year 1836 represented Jackson in the legislature, and was six times subsequently elected. He was also clerk of the circuit court of the county, and at the session of 1839 his seat was declared vacant in consequence of holding the two offices. He returned to his constituents, was re-elected, and presented his credentials without resigning his clerkship. This was refused, and he was again elected, and a third time rejected by the house. The adjournment of the legislature put an end to the controversy. Gov. Fitzpatrick appointed him agent of the State to adjust the two and three per cent. fund, and Gov. Collier commissioned him to adjust the boundary line with Georgia. He was also a presidential elector. His death occurred near Scottsboro in 1863. He was a matter-of-fact man, benevolent, temperate, and energetic."

While this bio does not address the issue of a colonelcy, I wonder if being "commissioned" to adjust a boundary line might indicate a military rank?