I can’t really answer the first and third one, you should contact scuba steve about them. What I CAN tell you though is that IMO flowable silicone is the best option if you want the yoyo unresposnsive.
yoyofool, the G&E2 is designed for pads not silicone. They came stock with a pair of Dif pads. SPYY shims may or may not work on it. The G&E2 has a different bearing seat than what most modern have. You could try those shims but I leave no guarantees.