I did RTFA, and he makes two real claims. His primary claim is that the iron dome system must be failing, because when the interceptor approaches the target from anything other than head on, the interceptor will fire its warhead at the wrong time. He implies that this failure is an inevitable consequence of geometry, but I don't see it. If you actually look at the diagrams, the interceptor has just a good a shot when approaching (say) from behind as from in front. In fact the odds look better to me from behind or the side, as the crossing speeds are lower and the shrapnel fan might actually run down the length of the target. The interceptor just needs to fire its warhead at a different moment. But his diagrams all show the warhead firing at the wrong time, for reasons that are not made clear.
Is the iron dome system smart enough to account for basic geometry? I would think so, since the problem is pretty simple, and the approach angle will be known by the radar even before launch. But I don't really know. And I don't think he does either.
His second claim might be more credible. He says that in hundreds of pictures of intercepts, only one clearly shows detonation of the incoming rocket. I don't know if this is true, and I don't trust his claim. But if it is true then it cries out for explanation.