Is Romania the only one Eastern-Balkanian country with over than 90% non-white population?

You information is incorrect. Here is the ethnic breakdown for Romania:

Romanian 83.4%, Hungarian 6.1%, Roma 3.1%, Ukrainian 0.3%, German 0.2%, other 0.7%, unspecified 6.1% (2011 est.) Source: CIA World Fact Book. Bookmark it; it's useful.