indeed secular governments of China and Iraq were siding with Serbs in their fight against Albanian Muslim extremists.
Then since we were in a cold war with Iraq at the time, an American 'national interest' existed in defeating Serbia. You have reversed the cause and effect. First NATO sided with Muslim extremists againts Serbs and only then China and Iraq started to help Serbs. BTW, both China and Baathist Iraq had an interest in supressing Islamists.