Can't add imported tree mesh to static mesh spawner

I’m doing a forest in pcg and I have imported a tree mesh from sketchfab in fbx format. I also added the textures to the material so it’s visible and looks right. But when I try to add it to the static mesh spawner node the mesh slot is just cleared(had a default pcg tree before). Can anyone explain what’s happening here?

This is the tree that I imported: