Hi, just wanted to mention how this was solved in case this happens to anyone else. The problem was I did not have the pool.cert file. The file was lost when I tried to retire the pool but the transaction did not go through. To solve this, the pool.cert file was recreated using:
with the appropriate file directory references and pool information.
After this I was able to retire the pool.
Thanks again to @Alexd1985 for coming up with the solution.