Instead of searching for experts who can tell you how wrong it is, why not look for research on the topic? There are a multitude of scholarly research studies on this topic in psychology and sociology that have shown that children raised with social nudity benefit from the practice.
Instead of assuming that children in a naturist environment are somehow at risk, why not consider the facts first? Clearly keeping kids dressed doesn't prevent abuse. Naturist environments tend to have stronger feelings of community than "normal" society. It is a group and family activity, which means that children are rarely left alone and vulnerable. Individuals with bad intentions within naturist environments are generally easier to identify. But most importantly, children raised as naturists tend to be more self-confident and not ashamed of their bodies. That means they are much more likely to say no and tell their parents when someone does things to them that they don't like. Doesn't that sound like a healthier way to raise children? It may seem like "extreme parenting" but naturists believe that it is actually the most normal way to be.
I realize that the topic causes people to react instinctively and emotionally instead of rationally. But I would expect a reporter to be able to get beyond that.
The Bare Oaks website has an entire page devoted to the topic of children in naturism. It contains answers to all the above questions and more:
Note: If the embedded video above doesn't work, you can view the 20/20 episode here: http://abcnews.go.com/2020/video/reamers-nudist-camp-family-naked-children-parenting-16283741