Jeez... getting a shiny charm is so hard. I wish I could just borrow one from someone. orz I really want to continue MMing but I dont feel like I should bother until I get my shiny charm.
Like JohnNiles said, the odds are pretty close with or without the charm when it comes to MMing. I've completed 7 MM hunts with the charm and tbh, I haven't noticed that much of a difference from when I was MMing without the charm. My current MM hunt is over 1500 eggs, so don't get your expectations too high while MMing with the charm. Good luck!