Groovy to transfer data between cube

Summary:

I planned to transfer headcount data between cubes by using groovy.

Content (please ensure you mask any confidential information):

I have tried to use datagrid definition builder to transfer existing and new hire headcount from WFP to FS. I am trying not to do multiple datamaps for this.

I planned to transfer all Ilvl0descendants(existing employees) into OFS_headcount and i did map to filter the count. I tried to remove at index [3] (if i replace it as OWP_Existing Employees only) but headcount gets replaced instead for same combination of cost center and entity.

Currently, my script is as follows to roll up the headcount for same combination.