See, in service PO, there are two pricing procedures are used.
One for Service PO and second for Service entry.
Have a look into these below screen shots.
First is PO condition, which you will find in PO - Condition tab
For this Pricing procedure, you will get the setting details in blog Pricing procedure Steps and Details in SAP MM
And second is Service condition , which you will find in service tab
Click on the condition
For this Pricing procedure, you will get the setting details in document SAP Service Configurations In SAP MM - Part 2
This Pricing Procedure is configured in the path as you mentioned.