Hi! Just a quick note--but my son did the exact same thing! He is 13 now and does go #2 on the potty so there is hope!
Since he did go #1 on the potty, I tried to force the issue and make him go #2 on the potty. After he did it once, he refused to poop for a whole week! I was freaking out and he ended up constipated, which was awful. I felt terrible! I remember taking him to the pediatrician for advice.
And here it is: "Don't worry about it."
When I whined "But if I keep giving him a diaper to go poop into, what will his motivation be to ever use the potty?!"
She said again, "Don't worry about it."
And she was right. You'll eventually get there. Just be patient. Good luck!