That's correct, on the frame givi has you use a threaded rod that it attaches to. The bracket that attaches to the frame also shares the same anchor point for the engine mount. The engine doesn't flex in that area anyways due to how it's mounted to the frame.
In my experience, the amount of vibrations are caused largely by the stupid spacer that connects the two halfs together under the engine. That damn thing is too small and just rattles around like crazy. People have commented that they thought something was wrong with the engine, it was that bad. I've tried rvt, sealant, etc. I eventually gave up and after a fresh dab of rvt, I zip tied it into place.