shin min reported he had quarrel with bride before wedding but suicide probability low
based on cctv footage speculation is this:
he badly needed to smoke, rushed out to fire exit but door is one-way so he couldn't come back and ran all the way down to the shopping arcade to find a way back to the main lift lobby so that he could get back to his room when wife finish shower
but how he fell remained a mystery, csi still checking
this one not tv show, need a long time to check all the angles to come up with a probable answer