Siebel 20.12 BI Report Based on Order and Sub Line Items for Handset Selling Voucher

Dear Experts,

I have a requirement to build a BI Report in Siebel CRM 20.12 to generate a Handset Selling Voucher based on Order and Sub Line Item data.

I would like to confirm if the recommended and only supported approach for defining Siebel BI Reports is by using a Siebel Integration Object.

If Integration Objects are required, how can we design the report to display Order-level details together with specific Sub Line Item details while excluding the Root Line Item?

For example, I have an Order where the line items contain a root line item called "Equipments & Commitments". Under this root line item, there may be multiple sub line items such as