Actually I tried... but i just can't. My 5* are too weak and 4 rainbows are not enough. I cleared the stage just by putting all the teams on the same path and I killed the boss with only half counter team (aka my last team) alive and Easter Cactus heal used.
I'm not at the point where I just need a bit luck. I just need an ally team to handle the remaning pest. But it will be different next time. I ill have 3 more rainbows (maybe 4 if I finally promote one girl and maybe even more if I'm finally lucky with gacha or if a nice 6* comes in a special gacha. Like Lavender reissue gacha maybe...).