You do realize that selenium toner will not act like a re-develop the halides rendered from the bleach as would the second bath of a bog standard sepia toning setup. So yes, if you want that bleached back look and you want to make it permanent, you will need to refix the print. The second run through the fixer will remove the halides created by the bleach. Essentially what you're doing is accomplishing in two steps, bleach and fix, what a Farmers Reducer does in one step. After a wash, you can then tone in selenium the remaining silver in the print.
It's an interesting concept, and one that I've never thought of trying. Might look good for a warm toned, high key type of thing.