Plot hole: The testimony at the beginning is dismissed as "hearsay" by the judge, but it isn't! It's eyewitness testimony under oath - the judge/jury determine how much weight it has as evidence, not dismiss simply because there's no physical evidence supporting it. The testimony itself is the evidence. Hearsay would be if the witness was testifying that someone else told him what happened. But he's saying he saw this with his own eyes - very different.
Plot hole: In the end Kincaid had to provide evidence against Dukhovich in court to uphold his end of the legally binding agreement from the beginning of the movie. Kincaid directs the courts to a secure website and provides a password to access the site which provides all the evidence needed. Kincaid could've provide that information via phone call or teleconference and never left his jail cell, negating all the unnecessary risk to law enforcement officials and himself.
Answer: You are right. It isn't hearsay and this is a mistake.