Fiori My Inbox with custom Popup to assign approver

In our custom workflow for JV Entries, we have a step were the initiator of the workflow enters the approver that they want the document sent to. This popup box happens when the user selects submit for approval from their inbox notification. The user enters the user id of the approver and the workflow continues from there.

The issue that we are having is in the Fiori My Inbox it is not working that way. In My Inbox, we have to go through multiple screens before the popup is made available for entry.

On this screen, the user would press the ‘Submit for Approval’ button

We then get a screen for the method and the operator must press the ‘Open Task’ button

At this point the popup that allows the entry of the approver appears. How do we get this popup to appear at the point the user press the ‘Submit to Approver’ on the first screen?

Thank you for any help that can be provided.