Thanks for the response. The above method I am aware of. Was more referering of a way to do the above but automatically. Either thorugh rest-api or by configuring config files. The wanted end result is the same as what you have described above but an automated way of getting there basically.
I didn't get your question. But I assume that you are trying to connect Splunk and Phantom through Phantom app in Splunk. For configuring Phantom in Splunk, goto phantom configuration and add the authorization token which you will get from Phantom.
You can get the authorization token from phantom:
goto Administration in main menu-> User Management-> user-> click on the 'automation' user., copy the authorization token and paste it in Splunk