This is a few months late, but I took it upon myself to find what a gum node looked like, as my island in C8 didn’t have any. Attached below is a picture of the tree and proof of it containing said gum. I apologize for any inconveniences, as I’m playing on Xbox, but I thought this would help.
https://gamerdvr.com/gamer/wallbarr/screenshot/16843574
https://gamerdvr.com/gamer/wallbarr/screenshot/16843586
edit: resource located in bottom left island of C8, Maidligan Holm