I'm not sure you still have the this issue or not. If you are looking for an opiton in 713+ Interaction portal, you can try this.
You can customize confirm button and add another action " Invoke Action and configure D_CPMPortalContext.ActiveParentRecent.pyExecute". This can bring up interaction screen and you can configure other action to close the confirm harness. Irrespective of which service case to be focused, with this change focus will be shipfted to Interaction.