As an 'investigator' who worked in the Balkans long after Medak, there was ample evidence that all three sides had units that were involved in ethnic cleansing and war crimes.
Ref the documents published by Serbs and/or Croat sources, after the war ended in 1995 all three sides were actively 're-creating history' to make themselves appear innocent and the others guilty (yes, including the Muslim Bosniacs). Special departments were created on all three sides to create documentation and testimy that would reinforce their claims of their innocence and others wrongdoing.
Its called 'disinformation' and 'propoganda'; people forget that the inhabitants of this area of the world learned their craft over the past 50 years from experts: the Russians, the Nazis and the extremist Muslim factions.
It is made worse by the fact that once information gets into the electronic information systems those who are unaware of whats going on, or who dont have first or second hand knowledge of events, dont know what to believe and are easily led down the wrong path.