Requisition Action details does not display if the approver was reassigned or delegated

Summary:

Is there any way to figure out if the approval workflow was altered by either reassigning the approver or due to delegation rule.

We have few old requisitions that should have been approved by a manager as per the approval rules set but action details show that it was approved by a peer at the same job level.

We need to figure out the reason for the same. Is there a way we can figure out that the approval workflow was altered and approver was reassigned or delegated.
Please refer to the below example. I replicated the PO in TEST Environment, skipped current assignment for the Level 1 approver and Reassigned Level 3 approver to Tarun. Now, how do we know if Tarun was reassigned and by whom. Please note: BPM does not show old requisition data.