But, Splunk.org doesn’t say anything about this. So kindly advise the best/ proven method for REST API approach. I am trying to get data from BOX.com api's (example: GET https://api.box.com/2.0/users) to Splunk. I am using Splunk Enterprise edition. It would be great if you can share your answer with an example.
That blog post you linked is from 2013. I highly doubt it works anymore.
On your other question, you were told to use a different app. You mentioned you couldn't get it to work due to proxy. Then you also mentioned nothing is being blocked between you and box. However if there was a proxy issue, then something certainly was blocked.