"Pike was arrested and the fort closed"

Didn't Pikes arrest occur in 1862? Hindman who was in command in Arkansas was engaged in rebuilding the entire Confederate Army in Arkansas after Van Dorn took every man and piece of equipment in the State that was worth taking, to Mississippi. That left Arkansas totally defenseless in the face of an 11,000 man Union army under the command of Gen Curtis that was attempting to march on the State Capital.

Pike was setting at Fort McCulloch an basically refused to send help even of those things which he did not even have crews for such as ten Parrot Artillery pieces. Even the regiments, which he was finally forced to send, such as the 19th (Dawson) Arkansas Infantry, He sent them without their arms and equipment, which still made them basically useless, since there were no weapons available in Arkansas, because Van Dorn had taken them all to Mississippi.

So Pikes disobedence to orders and self serving interest is what lead to his arrest and removal from command.