Commonly when we see solder balling, we think "too much paste." As a result, we pinch the apertures or change the shape to a "home plate." We don't think that's what's going on here.
But what if this component has a thicker solder plating on its terminations than we expect? This thicker plating could be combining with the routine amount of solder paste to result in too much solder that causes the solder balling.
Can you reduce the amount of paste that you apply at the pads for this component and then check for solder balling after reflow? For purposes of this experiment, just put tape across part of the apertures this component and print it.