Welcome to R2R. If it's a small patch of cyano, i'd just vacuum it out and monitor the system. If you are alway treating for Bryopsis, you've already made big changes to the water chemistry... which may have opened the door for the cyano. May be better to just let things stabilize and see how things play out. Cyano will go away once your water parameters stabilize.
To answer your question, IMO, I would only use one at a time. Both products can lower oxygen concentrations in your tank, so using both at the same time may be a bit dangerous for your inhabitants. I would get rid of the bryopsis first, since it is the hardest to get rid of. Just continue to siphon the cyano and then wait a couple of weeks after you are done with the fluconazol before attempting to treat the cyano. I would bet that the cyano would disappear on its own.
When I treated my tank with fluc. for bryopsis, cyano was an unfortunate bi-product. The bryopsis was toast though! I agree with other suggestions, what got rid of it for me was daily turkey basting of the rocks and sand and sucking it out during water changes.