Why does this SQL work on one version of MySql-Server but not another?
The datatype DATETIME used to be only yyyy-mm-dd hh:mm:ss.  But, beginning with 5.6.4(?), fractional seconds were allowed.  DATETIME(6) allows for microseconds:  yyyy-mm-dd hh:mm:ss.ffffff.

If you want that CREATE to work on both versions, remove the (6).  Notice how the error message pointed exactly at that.