came round the bend

that's what it means. Bend being a curve in the road.

You need to imagine yourself as a driver approaching a bend in the road which hides oncoming traffic. The car "on the wrong side" suddenly appears coming at you on your half of the road as defined by your national driving regulations.

A car "coming around the bend" simply means it is moving on the road on a curve in the road.

But the phrase "coming around the bend" can mean that something is moving ahead, after going through a turn. People can "come around the bend" when moving through an emotion, like trouble or grief. Someone may say, "I was having a bad day, but I am coming around the bend and getting better."

...only in your idiolect ! In mine, we would use "turning the corner". And we use "going round the bend" for "going crazy" /"is round the bend" for "is crazy".

Therefore, for a non-native speaker I suggest we stick to the context provided to avoid confusion.

Adverb, do you drive a car? ride a bicycle?

If not, you may need to watch a video clip to have that sentence make sense for you.

it looks like one of these vehicles might have been on the wrong side of the road when it came around the bend