AWT considers pilot wave as an analogy of Kelvin waves formed during object motion through particle environment. Original AWT explanation of double slit experiment is, every fast moving particle creates an undulations of vacuum foam around it by the same way, like fish flowing beneath water surface in analogy to de Broglie wave.
These undulations are oriented perpendicular to the particle motion direction and they can interfere with both slits, whenever particle passes through one of them. Aether foam gets more dense under shaking temporarily, thus mimicking mass/energy equivalence of relativity and probability density function of quantum mechanics at the same moment. The constructive interference makes a flabelliform paths of more dense vacuum foam, which the particle wave follows preferably, being focused by more dense environment, thus creating a interference patterns at the target.
By AWT the de Broglie wave or even quantum wave itself are real physical artifacts. The fact, they cannot be observed directly by the using of light wave follows from Bose statistics: the surface waves are penetrating mutually, so they cannot be observed mutually. But by Hardy's theorem weak (gravitational or photon coupling) measurement of object location without violating of uncertainty principle is possible. What we can observe is just a gravitational lensing effect of density gradients (as described by probability function), induced by these waves in vacuum foam by thickening effect during shaking.
Other thing is, whether pilot wave concept supplies a deeper insight or even other testable predictions, then for example time dependent Schrödinger equation does. By my opinion it doesn't, or it's even subset of information contained in classical QM formalism. This doesn't mean, in certain situations pilot wave formalism cannot supply an useful shortcut for formal solution (by the same way, like for example Bohr's atom model) - whereas in others cases it can become more difficult to apply, then other interpretations.