This is looks to be Ahmad Abd Alkarim Al-Hije (left).  He is the Commander of what was once known as the Ahrar al-Forat Brigade which was formerly allied with Ahrar al-Sham. They broke with al-Sham last year and joined up with ISIS. This picture was taken in Nuremberg, by the ‘Marriage Merry-go-round’ fountain.

(As with MOST things related to the Syrian migrant problem, there is no way to know 100% positively if this is the case however we’re 98% sure this is him.)