It was caused due to the fact that the unbeaching kernel activates by default when the windage kernel is used. The problem seems to be in kernels.py, on line 552:
(vel_u, vel_v, vel_w) = fieldset.UVW[time, particle.depth + particle_ddepth, particle.lat + particle_dlat, particle.lon + particle_dlon] # noqa
If the fieldset is not defined in 3D, it does not have the attribute "UVW", it has "UV" instead, causing the simulation to crash. Hope this helps!