You need to ask PG for a list of what RT uses what SFZ or better still they should put it in a column in the RealTrack picker.
Yes, I found some match pretty good and other are a completely different tone so you need to use an EQ matching Plugin.
Yes, the easiest way is put the midi on another track and use volume automation on the RealTrack.
Another thing you can do is use EZDrummer, EZKeys or EZBass and you route the midi out of them to the SforzandoVST with the sfz for the RT/RD.