Coastal Syria? Kilikia is not far from Syria, so why would the large Armenian population disappear? They couldn't've gotten lost! We're stubborn, sometimes arrogant but we are not that stupid.
And why would a 'scenic' route through the desert be taken? Couldn't a route through much more fertile and forgiving Armenian land be much more effective and would, in fact, be easier? Obviously, great inconvenience was had on the part of the irregulars who committed the crimes they were ordered to, showing that they meant to lead the helpless masses to their deaths in the desert, after, of course, all who could resist and many who couldn't were slaughtered wholesale.