Does the sum of the carbon footprint of all the products sold by a company equal to its total GHG emissions?

For the majority of companies, this is not the case!
Compare product carbon footprints with total company GHG emissions.
A company's total GHG emissions do indeed take these emissions into account, but other emissions are also accounted for. All direct and indirect emissions (upstream and downstream) must be taken into account. These include purchased services, capital goods, business travel, employee commuting, investments, etc.