You could have posted in the main thread for it.

But yeah... I haven't spent any kobans on restoring energy for fights (I only spend the 900 on a 10-spin epic pachinko (after I eventually save up that much from missions and contests), not on a single other thing that tries to ask for them) but the RNG has been kind of rough to me on this one as well. During all the previous events luck was with me and I had both event drops within the first few days of the event. In this event I did at least get Solveig within that time but I've been grinding away for Bonny with no luck since then. And there isn't much time left now.

Sooner or later it really makes you wish that the events could implement... I don't know...
1) some sort of "pity counter" which increases the odds bit by bit with each attempt?
2) some sort of event token reward drop that's fairly common but you can exchange a few dozen of them for an event girl?
3) some threshold where it's guaranteed after a certain number of attempts (set fairly high so you still have to really commit to it of course)?

Just something to ease off on the RNG to some extent. (Keeping in mind of course that they won't just give the girls away for no effort at all, it might still take some serious commitment throughout the event to earn the drops.)