If Europe doesn’t want an influx of a million more migrants, then they ought to send their own forces to help stop the invasion, and not expect Greece to be able to do it alone.
If Germanywere to announce it was sending an armored division to the Greek/Turkish border it would make a difference in Erdogan’s calculations.
From what I’m seeing the assistance might be from Bulgaria, Romania and Poland. The same cast of characters that fought 2 Balkan Wars against the Turks prior to WW1. History doesn’t repeat exactly, but it does rhyme.