Clean hospital beds and humane treatment...

It wasn't the SS; the liberation had indeed come. The whole thing is shown from the boy's point of view, and he was too weak to be aware of was going on: he was basically just carried around. Remember he had been lying next to a dead boy for two days? _That_ was the German version of the sick ward: nowhere near clean beds.

I thought I heard, toward the beginning of the movie, inmates talking about Germans giving good treatment to prisoners just before being sent to the crematorium....

Every man has two nations, one of them is France. (B. Franklin)

Once again: people, read the book. The camp had been liberated by that time.

I was confused by this scene as well. After re-watching, I don't think the camp had been liberated yet. For one, Gyorgy is taken to the hospital BEFORE the announcement is made over the loud speakers, calling for all S.S. to evacuate. However, there are some other signs as well. If the camp had indeed been liberated, he likely would not have been in the hospital alone with only one other prisoner. The allies brought in teams of medical personnel to treat as many people as possible and if the camp had already been liberated, the hospital would have likely been filled to full capacity, with doctors and nurses running around. The medical personnel would also be speaking English, not Polish, and would be treating his infection instead of just tucking him into bed and bringing him blankets and soup. The medical personnel would also likely have been filling out extensive forms, trying to ID all the prisoners.

What I think most likely happened is Gyorgy was taken to the shower room along with some other prisoners in the final days of the camp's operation. At the point, the S.S. would have been too busy destroying evidence, receiving rapid-fire orders from their superiors (or at least those who hadn't already fled/committed suicide/etc.), making escape plans themselves, and generally running around like chickens with their heads cut off to take any notice of the prisoners. In Auschwitz, the S.S. forced the majority of the prisoners on a death march, leaving behind those who were too weak or sick to participate. An S.S. unit was supposed to go to Auschwitz to kill everyone who had been left behind but things were so chaotic, frenzied and disorganized in the final days before liberation that the orders were never carried out. It's clear that this is near the end and the S.S. have other concerns besides the prisoners.

What confuses me, however, is why Gyorgy was placed on the train from Zeitz to another camp (after his knee had been "treated"), where he is immediately taken to the shower and then a clean bed. I'm not sure camp this is, although I believe it is somewhere in Germany since it was liberated by the Americans. Wherever he was taken, I do not think it had been liberated yet but the guards knew the allies were just hours away. It was likely total chaos, just like it had been in Auschwitz. I think what happened is, in the frenzy, a few kind prisoners decided to look out for Gyorgy, put him in the shower, get him into a clean bed, and hope he would make it to liberation, at which point the allies would take over and get him proper medical treatment.