You have no use for the headings tab because you are not properly using
Styles. That is shooting yourself in the foot.
If it is already in the Results pane, it should stay there. If you close the Navigation Pane before starting your search, Ctrl+F will go to the Results pane.
I added a keyboard shortcut to toggle the Navigation Pane, using Ctrl+Shift+N (instead of apply Normal Style). I can use that to close the Nav Pane if I want. The command is from the View Tab and is NavPane.