I don't think it's topping from the bottom for the submissive to let her dominant know: "I need this" or "I need this from you". The dominant isn't all-knowing, so there will always be situations where, once it's explained, we'll say: "Well, shit, I thought the exact opposite."

Have you explained your need for absolution to him in that way? If not, he may not understand it fully. There's a tendency in dominants who haven't quite accepted that punishment is the "right" thing to do to want to make up for it somehow.