From the time we had these missions, I know that I got petals from Bergamot 6-4 and 6-5.

I tried Banana 6-4 a few times because the 3 chests are assured, then switched back to 6-5 but still nothing after ~400stam.

Since the current event is a raid boss, we have time to try this, but I'm afraid I will spend a lot of stamina potions ^^