When they say a VST kit, they mean a VST sounding kit. I doubt very seriously there will be any kind of VST control in the module other than the effects that are already in there. In a way the DM10 drum module already has VST like controls in it. I can control the volume of each sound, I can change the pitch, I can change the eq., there is the velocity envelopes, and the effects.
I think what they mean by VST sounding kit is the depth of each kit. Right now the DM10's samples only have about 3 or 4 layers deep of samples. Meaning a snare sound is made up of 3 or 4 different velocity sounds. In a VST kit, they normally have up to 12 or more layers of velocity sounds for each instrument (like the snare) That is what makes VST sound more real. Since the DM10 only has 128MB of memory, to put 12 or more velocity sounds per instrument takes up a lot of space.