Conduct Disorder is a diagnosis given to children and teens under the age of 18, and to adults over 18 who meet some but not all of the criteria for a diagnosis of Antisocial Personality Disorder. The personality disorders are generally not 'diagnosed' before age 18 partly because they depend on observation of a pattern of behavior over years, and of functioning that seriously impairs an individual's ability to manage in adult life.
To add another point of view to the discussion, I would certainly think about how your child was diagnosed, and whether sufficient time was taken for evaluation. But if this was done carefully and other diagnoses were considered in the differential, I don't think the diagnosis should be rejected simply because your child is only ten. While diagnoses can change over time, and traits that meet criteria for Conduct Disorder may and usually will become traits that suggest another diagnosis as an adult, it is important to manage the current problematic behaviors appropriately.
In the case of a child with CD, usual parenting methods such as love and logic, 123 Magic, and even the methods in The Explosive Child, just don't work. These are great parenting programs, but they aren't the right approach for a child who sees interactions in terms of power, who isn't bonded to an authority figure (for whatever reason), and who hasn't developed true empathy for others. They all assume basic reciprocal values and patterns of behavior that may not be present in a child with CD.
We tried every program out there, including Ross Greene's program, with our difficult child. None of them worked. They were the wrong treatment. Unfortunately, using the wrong treatment allowed our difficult child's behaviors to worsen until our home was a nightmare. The only methods that had any impact were given us by a therapist skilled in treatment of attachment disorders, but by that time our difficult child was old enough that we could contain, but not alter, his behavior patterns.
Getting more testing, i.e. neuropsychologist testing and so on, can give more information and information is always good. But you have to cope with behaviors now, every day. What has your doctor recommended for managing with your difficult child on a daily basis?
{{hugs}} and warm thoughts. You are not alone in this. Feel free to pm me if you want.
