Business partners: history of changes including release user

Dear all,

The audit is requesting a proof indicating the user who created a business partner and the person who applied the 4 eyes principle (release worklow with 2 employees)?

They need to see the proof that a 4 eyes principle is applied in the frame of BP set up.

I know BPCD transaction but it does not show this user who release a BP change.

Many thanks for your help.

Brgds

Philippe.