Thanks for kindly posting the account of Col Colquitt's death at Chickamauga.
To answer your questions, the 46th Georgia Regiment served along the Georgia and South Carolina coast during its first year. In early May 1863 the regiment went to Mississippi with General States Rights Gist's Brigade.
Here's the link to the Columbus Museum --
Note the image of Horace King, an African-American who built the bridge at Columbus over the Chattahoochee River.
The name T. C. Stanley appears among service files of this regiment. His rank is given as chaplain. Let me know if you have other questions.