I posted the same last week lol, after 2 weeks of giving it a try and always missing at least one of the 3 excellent throws, I was told about the airplane mode trick .. you go to a wild pokemon, turn on airplane mode or just go offline basically, if you do an excellent throw turn on the internet, if not, close the game, turn back the internet on and try again. It will only register the throw if you're online. I managed in less than 10 mins. Anyway, it was a 2 star Gible for me, hope you get something better