Join Curves Not Working

Hi so I have a tree with branches and 3 curves on each branch. I want to join these curves and then make a surface from them.

The problem is that the join curve component works on some of them but not all.

What's more frustrating is if I bake them into Rhino and join them there it works! >:(

Anyone know why they won't join in Grasshopper but they will in Rhino? I'm attaching the relevant portion of my file to this post.