Whether they're actually wrong depends on how you interpret what they wrote. Maybe they aren't talking about the winning probability (which indeed is 99%) but,

Whether they're actually wrong depends on how you interpret what they wrote. Maybe they aren't talking about the winning probability (which indeed is 99%) but, literally what they wrote, the odd of one of two remaining doors being the right one. This will explain why they took this modified problem rather explaining the common one in full. If that is then it's still not good because they passed the interesting part.