How to get Object Name1 of workflow log from workflow container

Hello,

Now i need to write a program exit for copyed standard WorkFlow:WS01700048 which is for credit limit change.

This workflow is only one step, I can get everything i need except one field called credit segment which i find it store as object name 1 at workflow log.

I didn't find it at workflow container or related BOR. could someone tell me how to get this from workflow container?

Here is the front-end screen, when it been saved, that workflow will be triggered. Below is its workflow log which can get this field as object name 1.

many thanks,

JG