Has anyone deemed qualified by the local building department determined if what is supporting the existing roof will also support the proposed roof, dead and live loads?
Without knowing a lot more, nearly impossible to say for sure. What kind of building is the pro shop? Block, stick, metal? Attaching to eave or gable or other? Probably those wood 6x6s need to bevind footings below frost line. And more.
We're I wagering, odds might be ever so slightly in your favor - but just as much of a guess as to what make of car you own or your dad's first name.
You really need an architect or engineer to answer this for a commercial building. Some builders might be able to tell. Frankly if your building department doesn't require an architect or engineer, i'd be worried. And if you're skipping the building department and permit, this is not the place to ask.