Per call C10952765 : Cannot find volume of the solid volume due to removal pro_compute_volume() function...
PTC tech support reply:
First of all, I apologize for the time taken.
The only way I see which may help us in this case is, build the application after including the prodevelop includes and libraries from Creo Elements/Pro 5.0. Please ignore if you are already aware of this.
I suggest you to submit an Product Idea requesting equivalent function(mentioning the use case) in order to evaluate this functionality for future releases by PTC product management.