Eureka !!!
Starting from Google lens going via a Wrong commercial name as Kokum Phool I finally landed on a whole blog post appropriately written about this fruit with more pictures.
Here is the blog post
http://ourfarmatchitrapur.blogspot.com/2018/03/vatambavatamba.htmlAttaching two pictures from that Blogpost.
The plant that I am referring to is exactly same as detailed in the blogpost.
However there is no clarity about Botanical name.
Two names came up but both seem wrong to me from the Photos on Internet.
Garcinia cambogia and
Artocarpus lacucha
The correct Konkani name is वटाम्बो , ओट and ओकांबा I wrote earlier seem to be local distortions