I believe that realistic representations of the Holocaust do in fact honor the suffering of the victims by the very act of recording the horrors that took place, and thereby memorializing the people who have experienced them. It is much worse for atrocities to go unremembered or to be denied than to have them depicted even in the most painful detail. To illustrate this, briefly, I'll refer to two classic books, Elle Wiesel's Night and Edward Lewis Wallant's The Pawnbroker.
As a survivor himself, Wiesel of course had every right to detail his own experiences in the death camps. But one of the most important things Night attests to is that even as late as 1944, much of the Jewish population of Europe was still unaware of what was happening at Auschwitz and the other camps. When the Jews of Sighet, Wiesel's home town in Hungary, are deported, they at first cannot believe they are going to become victims of mass murder, of genocide. Wiesel's account of this is a warning to future generations that any atrocity or horror is possible, and can and will be inflicted upon innocent people when evil men are allowed to take power and are not stopped.
Wallant's The Pawnbroker is a novel centering on a Holocaust survivor, Sol Nazerman, who, though functioning in the new life he has built for himself in the US, is suffering from what we now know as PTSD--Post Traumatic Stress Disorder. We can here see a link back to Wiesel's account of himself as appearing like a living corpse when he looks in the mirror after liberation. Nazerman too, like many other survivors, is experiencing a kind of living death, cut off from emotion by his lasting trauma. It's chiefly through narratives such as Wiesel's and Wallant's that others can reach an understanding of the suffering of Holocaust victims and the survivors of other genocides and traumatic events. Through the sympathetic portrayals in such depictions, the victims are fully honored.