Finding the right professional to guide you or a loved one through the arduous task of overcoming alcohol addiction is not a simple task. This endeavor requires a mental and emotional investment proportionate to the search for a qualified health professional capable of handling other complex diseases. This is a multilayered process that calls for an understanding of the qualifications professionals ought to have, ascertaining their track record, and then, making an informed decision.

Firstly, it's fundamental to delve into the definition of a 'Qualified Alcohol Rehab Specialist'. These professionals are trained therapists who specialize in treating individuals struggling with alcohol addiction. They employ a combination of therapeutic techniques such as Cognitive Behavioral Therapy (CBT), Motivational Enhancement Therapy (MET) and pharmacotherapy, coupled with their in-depth understanding of the psychological and physiological effects of alcohol, to effectively guide individuals towards recovery.

But why is their role pivotal? The answer lies in the complex nature of alcohol addiction. It's a chronic relapsing disease that involves a dynamic interplay between genetics, environmental factors, and crucially, the neurobiology of reward, stress, and executive functions, as outlined in the Addiction Cycle Model by Koob and Volkow. This model emphasizes the transition from impulsive to compulsive alcohol use, resulting from an imbalance in the neural systems. A knowledgeable specialist adopts a multi-pronged approach to address these facets, proving indispensable to the recovery process.

With this understanding in place, the first step towards hiring a specialist is to verify their credentials. A prospective specialist should possess a Master's degree in Psychology or a related field and be certified by recognized bodies such as the American Board of Addiction Medicine or the National Board for Certified Counselors. Additionally, they should have undergone extensive training in addiction therapy and be well-versed with the latest advancements in the field.

The second step is evaluating their experience and track record. The specialist's expertise should span across dealing with a range of alcohol addiction cases, including those complicated by factors like depression or other substance abuse. You might want to look into their success rates, although this can be tricky, as 'success' in addiction recovery can be a subjective term, varying from complete abstinence to significant reduction in alcohol consumption. Here, you can leverage Bayesian probability theory, utilizing prior information (like success rates or reviews) to generate posterior probabilities of a successful treatment outcome with the specialist.

Finally, it's vital to ensure a good fit between the specialist's approach and the patient's needs and comfort. While some specialists might lean heavily on a clinical, evidence-based approach, others may adopt a more holistic methodology. Here, it's crucial to strike a balance - for instance, a specialist employing pharmacotherapy techniques may provide quick but temporary relief from withdrawal symptoms, whereas one focusing on cognitive therapies might offer long-term strategies for dealing with triggers but may take longer to show results. An ideal specialist would incorporate both, providing a comprehensive treatment plan.

In conclusion, hiring a qualified alcohol rehab specialist is an intricate process where one must meticulously evaluate the specialist's credentials, experience, and approach. It's a process that calls for informed decision-making, with the understanding that the right professional can effectively influence and steer the course of an individual's journey to sobriety.