That's what I was going to say, too, as it doesn't seem anyone else has mentioned that this will be a trio. If you can't get the first one, you can't get the final one. :/
I just got it on my older account with basic Frostfang and Pandaffodil. Now I can go back to breeding for the forever elusive (on both accounts) Ladypug. My newer account has produced 4 Storm Sphinx; my older account, zero.