To respond to the question in the original post, I find the priest's informal comments in the context of the Sacrament of Holy Confession, deplorable.
I've heard plenty of priests use slang, and very rarely, swear; however, even amongst themselves, priests do not swear. An Orthodox priest once told me about a Christmas luncheon of the suburban ministerial association of which he was a member. He told me a new Lutheran minister, a female, was attending and meeting the members for the first time. He said she was swearing quite a bit. He and the Roman Catholic priest he sat with shook their heads together; they felt she was trying to act like "one of the boys," not really knowing that Christian clergy do not swear.