I dont have screenshots to throw in here but I will chip in with my experience. This is just my personal experience not advice one way or the other so hopefully it wont be taken down for "drama". But personally unless picklejuicy comes back I do not trust the numbers and claimed drop rates given here or discord.

In a fateful choice event kushina summer was stated to be around 13k coupons to recruit, I spent 18k and only got enough points for 30 frags

I got a jackpot x from slot machine and was told instead of getting shisui directly it would be better to take the coupons, wait for a good cycle and that I could get shisui for under 100k from capsules plus rewards from any fuku at the time. I already had coupons saved before the jackpot so I could afford to be a bit careless and test. Over 2 capsule events and roughly 9 different shisui boards 55k coupons got me just 13 frags.

I also went for edo itachi because I only needed 3 frags to 4 star him, I refreshed until getting what the mods told me was a "good" board, i spent 10k coupons and got just 2 frags