Marjorie --
No members of Darden's Mississippi Battery or any other Confederate command were present at Citronelle. General Taylor signed a surrender agreement with General Canby there. Taylor returned to his headquarters at Meridian MS to inform his officers of the agreement. Federal officers soon arrived to issue paroles for Confederate troops. From your statement it sounds as if paroles were issued to Darden's Battery on May 11th.
These were paroles, not pardons. The men of Darden's Battery were not criminals in need of pardon. President Johnson pardoned former Confederate citizens whose property values were estimated at $20,000 or more.