@anon78309838 That did it 
Huge thanks!
For future readers who want to accomplish the same thing:
- I turned the Recommend button into a list of users, filtering based on the Current Provider then Managed by (which is the user field I wanted to access)
- Then in the actions when that list item is clicked, I add the Current user to the Following field for the Logged-In user
Be careful: I was confused for a while as my click actions on the list didn’t seem to register but I realized I was still applying the click actions form the list and not from the (now list item) button. So be mindful of that!