WEEKDAYDIFF values not populating when comparing project default baseline start dates to go-live task default baseline completion date

I have a task report built that is correctly showing me two date columns. I want to compare these 2 dates using WEEKDAYDIFF. These are standard fields and values but the valuefield has been customized with text mode.

• Column 1 - Default baseline planned start date for the project
  

  • displayname=Project Baseline Planned Start Date
    
    querysort=project:plannedStartDate
    
    valuefield=project:defaultBaseline:plannedStartDate
    
    valueformat=atDate

• Column 2 - Baseline completion date for the go-live task 

• displayname=Baseline Target Go-Live
  
  linkedname=defaultBaselineTask
  
  namekey=view.relatedcolumn
  
  namekeyargkey.0=defaultBaselineTask
  
  namekeyargkey.1=plannedCompletionDate
  
  querysort=defaultBaselineTask:plannedCompletionDate
  
  valuefield=defaultBaselineTask:plannedCompletionDate
  
  valueformat=atDate

Trying to calculate the difference between these two dates on a Task report using these column details in a "Week Day Difference" column.

• displayname=Week Day Difference
  
  valueexpression=WEEKDAYDIFF({project:defaultBaseline:plannedStartDate},{defaultBaseline:plannedCompletionDate})
  
  valueformat=HTML

Trying to see how long the duration should have been when the project was created/baselines were taken - Project start to go-live task completion . I have read forums and guides but cannot figure out why this is showing up with no data. 

Screenshot of my report with the columns showing values is attached