Playing media file AFTER other media on slide completes

Good afternoon.  I need suggestions and help getting the audio, Markers, and audio triggers to function as programmed.

I am using Markers instead of adding layers for each.  I did the "Play Media" trigger when all are "Visited" without achieving what I expected, based on what worked for me before.  Added the "Click Next" audio file as a layer and still not getting the desired results while using Markers, which are basically buttons/shape.  I have done it with buttons, hotspots, etc.

My goal is: Let the learner go through the main content of the screen; then, cue them to click each of the markers to access additional information.  After visiting all markers, have the Click Next audio play.  That will allow them to move to the next slide once the click next on cue.

I am all ears.  Thank you in advance.