The person who screens you who was supposedly a developer in the past. They weren't able to answer a simple OOP question. The tech questions they asks you are on their screen (you can see them reading them off). They don't know them off the top of his head like a real dev would.
The person doing the tech test doesn't have an understanding of Java best practices or principles (encapsulation, immutability, thread safety, proper access modifiers, etc.). If you want the job just agree with them even if they're wrong. It's not a trick test. The person just doesn't know what they are doing. This is more of a personality test rather than a true tech out.