Query Where Used within Item Type Relationship

Our MCO process requires that we show all the affected items based on the parts that are affected. I'm wondering if the query I have below is possible? I would like to use this as a reverse grid look up within a tab. With the testing I have done so far I can't get it to work the way I want it to. Is there a different way I go about doing this? The main thing is I need to be able to export this as a report. Thank you for your help its greatly appreciated. 

 <Item type="Simple MCO" action="get" id="{@id}">

        <Relationships>

             <Item action="get" type="Simple MCO Part">

                     <related_id>

                            <Item type="Part" action="getItemWhereUsed"></Item>

                    </related_id>

              </Item>

           </Relationships>

</Item>