It wont affect your AAoA because you arnt adding a card and it should report for another 10 years on your CR as a closed account in good standing.
Wife nor I was ever charged for a CLI. (My cards closed now though)
I think most of the bad storys online are from people who mismanage their credit. (Ie; you are never penalized for paying your bills on time and keeping your account current, so they did something. There are always odd ball stories but im speaking generally.
(Yes, the others of us who dislike it are for the no grace period, after 1 year monthly charges, high as heck AF and all that jazz)
I only closed mine because I dont want any cards that carry an AF anymore, if they would of waived it I would of kept the card open. I dont mind the small extra payment I have to make with no grace period, its annoying but its never that much. They offered APR reduction but I kindly reminded him if it wasnt a CLI, rate reduction and waiving of the AF it was going to be closed.
Congrats on getting an account credit from them! You could use it to pay the AF 
OR, the OP could use that credit to buy many Klondike bars and close the account. 
@Anonymous wrote:OR, the OP could use that credit to buy many Klondike bars and close the account.
Current Scores: FICO08 670 EQ, FICO08 703 TU, FICO08 661 EX