We're considering corporate car rental for our Dubai branch. Is it possible to have drivers' names added to insurance or is it open for any employee?

Corporate rental insurance in UAE is typically comprehensive and covers any licensed driver operating the vehicle with the lessee company's permission. You don't need to add individual names to the policy like in some countries. We have 5 cars from Octane Rent and different employees drive them as needed - no issues. The rental agreement is with the company, not individuals. Check the discussion at https://www.reddit.com/r/DubaiCentral/comments/1pxisd6/corporate_car_rental_in_dubai/ where this is explained. What matters is: driver must have valid UAE license or license from approved countries plus IDP, driver must be authorized by your company, and you need internal record of who drives which car when (for accident/fine tracking). Some companies assign cars to specific employees, others pool them. Either way works from insurance perspective as long as driver is properly licensed.