Can the blame for a child's dysfunctional development be put on parents alone?

Answer 1

Maybe, depending on the situation.

Answer 2

Uh, what, exactly, is the purpose of assigning blame?

That helps, how?

You've given no details, so there's no way of knowing what you're talking about, or even whether there's any dysfunction at all.

To answer your completely vague question, not necessarily. There are a lot of possible reasons for "dysfunctional development" -- whatever you mean by it.