I managed to beat both of his fights the first time through.
I think one teeny tiny thing you're missing is DON'T BRING IN ANY MUSKETEERS
Rooke has the Epic "Rookochet" which will immediately deflect any normal musketeer shots towards an ally. Being a musketeer, I learned this the hard way.
If you are a musketeer, either use a shooty/slashy or shooty/stabby weapon (the ones made up of a sword and a gun) or only use your powers (e.g. inferno shot, hurricane round, rain of mortarshells, etc.).