At multiple points in this article, the students feel sadness or trepidation in dealing with these sick children. Yet (some of the students) can rationalize their way to depersonalizing the children. Nope. Their emotions are correct. They feel sad and hopeless because they see sick children suffering. They know that this is what they see. Yet they try to "get past that" and talk about "ethical decisions" in which the children are either not human or not really living at all. Fools.
I tend to agree with you: their initial reactions and emotions are valid. Philosophy tends to give them the means to rationalize away those emotions and see the situation without the emotions that make us human. To be overly emotional wouldn't be helpful and to be without emotion wouldn't be human. Being able to decide with both one's head and heart should be the result of a philosphy class, imho.
I also think that part of it is that they feel intimidated by Singer and want to please him. After all, he is THE Peter Singer. (If you could hear me say that, you would hear the scorn in my voice.) It's a shame that they are willing to give up their humanity for a grade.