Hull KR's Kris Welham intercepted a poor Ben Jeffries pass 70 yards out to convert before two tries from Michael Vella saw the visitors 18 points up and Bradford rocking on their heels.
Louie McCarthy-Scarsbrook was stopped just short of the line, but Danny Orr quickly sent the ball wide for Howell to set up Gafa before Esders, currently on loan from Hull KR, followed him over moments later from a Luke Gale pass.
Hull KR's best moment came when Jake Webster intercepted Sean Long's pass, but Pryce used his pace to haul the winger down on the half-way line, much to the delight of the Knowsley Road faithful.