I need help with building a formula column in a report as follows.

Scenario:  Use an IF or CASE statement to create groupings based on a Project Manager name. 

• Report is based on the Project object
• Attempting to create a Formula Column based on the Project Manager field:
  1. If Project Manager name is “John Doe”, return “Group 1”
  2. If Project Manager name is “Jane Doe”, return “Group 2”
  3. If Project Manager name is anything else, return “Group 3”

Issues Encountered:

• Cannot use the $ProjectManager field in an IF statement, because it is a ‘Reference to Object’ type. This means it is necessary to convert the field to a string, yet there is no ToString() option in Reports?  
• Cannot use the $ProjectManager.FirstName or $ProjectManager.LastName fields. It gives an error “You can only select fields from the current object”. Why even provide an option to select fields that aren’t available to use? 

I can’t think of a more basic formula to create, and AdaptiveWork is failing me.  Is there some workaround that I’m supposed to know about. Would love to know what I’m doing wrong.

If this is an actual limitation that would be embarrassing for the AdaptiveWork product-- as the Sales team likes to show off all the flexibility and robustness the Reports feature.

Thanks!