You should have your users that can delete asset belong to a workflow user group so they can invoke WFs. As Far as the Delete button, you need to document to your users to invoke the TrashAsset workflow to remove assets, not use the Delete button.
To delete assets using this WF - you need to have a user select the asset from the Asset view.

Select the Workflow button - not Delete button and select the specific workflow.

Once done, the Asset is placed into the Trash folder.

and the original asset is deleted.
This is the best way to achieve your requirements. Adobe does not recommend trying to reverse eng the Delete button, etc, This would not be supported if something broke. This is exactly why Workflows were added to the product. Use the tooling that is part of AEM.