Maybe you're better off using the official packages instead. You can find them on https://packagecloud.io/varnishcache/hitch.
These packages are maintained by Varnish Software, contain a more recent version of Hitch, and are regularly updated.
There are Ubuntu packages available for 16.04, or more recent versions.
The following commands will get the job done:...
The listen mydomain.co.in:8080; directive in your Nginx config is probably the issue.
Nginx will only listen on the network interface for the IP that is resolved by the domain. I'm well aware that the domain is redacted for the sake of privacy. But you probably know what I mean.
This is also reflected by the 184.108.40.206:8080 local address in your netstat ...