As long as you have a booking number from the cruise line you are in good shape. Also, the fact that you already received one refund from the travel agency says a LOT for their honesty and credibility.
But that does not change the value of the advice offered (to other people who may read this post) by Pete up above.
I am the editor, but I also speculate, ask questions and play devil's advocate. I reserve the right to change my mind.