I need to clone a line item; however, I also need to clone some fields that are not listed in the table. Reason being is that we have a formula field that is a summation of a bunch of net rate fields, and a workflow rule that makes our amounts field equal to that summation.

Problem is when cloning records in-line, the amount is cloned yet the core net rates are not. So when the workflow rule runs on record creation/edit, it makes amounts equal to the sum of net rates which are zero. 

We need to be able to clone in-line records and have these net rates in the background clone as well, yet putting each of them in the table would take up too much screen real estate. 

Is there a way we can clone the in-line record as well as the background net rates so our rule works?

Also, we have snippets for cloning line items which work perfectly, we just need to work around that workflow rule so the In-Line clone function also clones the fields in the opportunity not listed in the table.