The alert actions 'Sent to Phantom' and 'Run Playbook in Phantom' are for Splunk ES. I am only using Splunk Enterprise.
From the Phantom docs:
"If you are running the Phantom App on Splunk on a Splunk ES server, then additional options are available to you. You can use "Send to Phantom" and "Run Playbook in Phantom" as alert actions, and you can send notable events to Phantom as an Adaptive Response Action.
Note: These alert actions will show up in the interface on regular Splunk (non-ES), but they ONLY work on Splunk ES"
... View more