I'm in the Other Quebec Deductions Profile. Should I check the 'Deduction for workers' line and add the Provincial Tax amount that I see in my payslip?

TurboTax automatically calculates the deduction for workers for you based on amounts from your federal t-slips and relevés. So, you don't need to enter anything on that page unless you have one (or more) of the types of non-eligible employment income listed on the page.