Interactive drag-and-drop not accessible for keyboard-only users - won't tab to content
I'm building an accessible drag-and-drop interaction in Storyline 360.
I've added triggers to all the drag options (text in shapes) so they can be selected and moved to the target (a large hotspot) using a keyboard.
I've created a custom focus order so the user can tab through the drag options and then go to the hotspot.
However, the drag options are not highlighted by pressing tab - it goes from the hotspot to the submit button and won't select any of the drag options. I'm assuming this is because they're text boxes, which don't count as interactive elements. However, I've added multiple triggers to each one (and they are not grouped), so surely Articulate should acknowledge them as interactive elements?
Any tips or ideas to get this working for users of both screen readers and keyboard only? The training will be used by everybody in the organisation.