I don't know exactly what he was referencing but the easiest way to verify the authenticity of points on issues where there tend to be two sides saying mutually incompatible things is to look at the overlap of what they both say is true. That is going to usually be true. And all it takes to find that is to look at sources for both sides.

Expert vetting doesn't even touch the underlying problem, because the pursuit is not expertise, in and of itself, but objectivity. And that's something far scarcer than expertise, and increasingly fleeting in today's world. A Chinese expert is probably going to have a different perspective on e.g. the Uyghurs than an America expert on such, even if both are in no way trying to mislead but giving their most sincere analysis of the situation.

Even on topics that are not conventionally controversial, you'll find a similar issue. Ask two astrophysicists of different worldviews on dark matter, and you are going to get two very different answers that, in many ways, will be incompatible. Simply "believing" one over the other doesn't really make any sense, nor does randomly polling astrophysicists and taking that as the definitive truth.