Even though there was a sign saying right of way, that by common sense means at the time of entrance. He IMHO was further into the tunnel evident by he was in darkness while she was in sunlight. Any sunlight upon him was from her side of the tunnel.
I ponder that right of way may have been more tradition than any kind of study with modern traffic. It is obvious the tunnel, which is through a bridge, was built even as far back as the 1700 or 1800's. Could that right of way have been established with horse carts, carriages, and buggies?
I don't think he was lost. As the article pointed out he had a fear of backing up. Too, he did have a greater length to backup. Could that be why only two were addressing him seeming more consoling? Could she also have the fear of backing up, being passed on the roadway, or was she stuck on the sign saying right of way with stubbornness?
The crowd was very confrontational with her. One woman declared if something happens to her family because of the standoff it would be her fault. There were many more addressing her to move. The man who used expletives pictured seems to have some official capacity. Unsure.
Answering what I would have done is backed up while flipping her the bird the whole time. And, I would have been courteous allowing the growing line of traffic on her side pass by too. That to me meant it was logical for her to let his lone car pass by before a stream of cars on her side after the fact of the standoff occurring. Would that have been simple courtesy having more power than the stubbornness associated with a sign? The crowd seemed to think so.