If the pilot waves are observable directly (beyond just the forces they impart on the particles) then it changes the character of the theory completely. Such an observation would be an enormous news in the physics world, as it would take this theory from the realm of QM interpretation to QM extension, i.e. this would be a theory that can predict observables that QM cannot. If that is the case I would agree that it stands on firmer ground than orthodox QM.