You can decide to assign combat damage to the defending player or planeswalker even if the blocking creature has protection from green or other damage prevention effects applying to it.

Proud Wildbonder’s last ability applies to itself as long as it still has trample.

When assigning combat damage, you choose whether you want to assign all damage to blocking creatures and assign trample damage from that as normal, or if you want to assign all of it to the player or planeswalker the creature is attacking. You can’t assign some damage to one blocker then skip other blockers.