Ferguson and his brigade remained in Georgia until some time in March 1865. At the end of the war, Brig. Gen. Ferguson was exchanging correspondence with Jefferson Davis, then at Charlotte NC. Ferguson and his command formed part of the escort for President Davis and his party from Charlotte to the Savannah River.
You would do well to consult the Official Records for mentions of Brig. Gen. Samuel W. Ferguson and his brigade. The 56th Alabama served under his command from the second half of 1863 until the end of the war. Another helpful option will be to consult unit histories and articles on other regiments serving in Ferguson's command.