Thank you for leaving a review with Viator. We wanted to make sure we clarified a few points, so future travelers will have the best possible information. As Viator is a Tour Broker, we use multiple Tour Operators around the world to be able to supply the wealth and variety of tours that we have. You will mostly likely never see a guide or driver while in a destination who will be wearing a "Viator" shirt - they will likely have the name of the local Tour Operator.
We always provide the Tour Operator information to you on the voucher, and most of tours include directions for reconfirmation. (Depending on the Tour, there are rare instances where you do not need to reconfirm.) The reconfirmation process is to ensure that you get the exact time of pickup, and directions on how to find the Guide or Driver. This process also allows you to ask any questions you may have, or get good turn by turn directions if you should need them.
We're glad to hear the Tour Operator was able to be flexible and send you a new driver. For future tours, we would recommend that you always read the directions listed under the "Important" section of your voucher, to ensure that you have the best information concerning the Tour Operator.