I think you are exactly right! This spear is indeed a pretty damaged example of a Vanuatu spear.
I have copied the article you are referring to below
http://web.prm.ox.ac.uk/weapons/index.p ... index.html
VanuatuSpear with bone head from Vanuatu, Oceania. Part of the Pitt Rivers Museum Founding Collection. Given to the Museum in 1884.
This finely-made throwing spear is from Espíritu Santo Island in Vanuatu, an island nation in Melanesia. It measures 2.5 metres in length and has several rows of bone points, which may have been tipped with poison. Spears of this kind were found throughout the region, from the Solomon Islands in the west to Samoa in the east.
The points are secured in place with coconut cord and are in fact shards of human femur (thigh-bone). They may well be from enemy remains as part of the humiliating subordination suffered by defeated foes both before and after death.
Melanesian warfare was less violent than that of Europe and since honour and responsibility were at stake, battles rarely resulted in many casualties. This impressive and terrifying spear was used more as a visual deterrent than an actual weapon and so contributed to minimizing the loss of life.