I’m making an argument about the validity of an argument. A rebuttal to that can never be “but the conclusion is true”.

It's quite clear if you approach these things logically that Chalmers doesn't do a lot of thinking before coming up with these arguments. All of his arguments boil down to "if we assume that consciousness is different from everything else, then it's different from everything else". He gets way, way too much attention for someone who is sub mediocre in his reasoning.

He also doesn't understand what computation is, even though he often makes confident statements about it. He thinks computation is a subjective process, that something only counts as a computation if someone interprets it as such, which is simply wrong, not a debatable topic. And this is the core of one of his other arguments about why consciousness can't be a computational process.

There are a number of ways to determine that consciousness is not a computational process. Roger Penrose is a good source on this.

There is not. It's by the far the most likely explanation, and even if you don't agree with that, it is at least completely consistent with everything we know about computation.

For one, you would have to determine whether physical laws are computational processes. Stephen Wolfram is trying this, but it requires some incredible assumptions.

The laws of physics we know right now are either computable or stochastic with computable probabilities. This was of course the only possible outcome if physics made any sense at all, since the purpose of physics is to compute outcomes, so a physical theory that was not computable would never have been invented.

Still, the laws of physics could be anything and it wouldn't matter for this question. The only relevant question is whether our brains are computers, regardless of how the physics work at the lowest level. After all, we have clear proof that you can make computers on the existing laws of physics (I'm typing this reply on one!), so all we need to know is whether our brains are bio-chemical computers. Neuroscience is nowhere near a level where it can answer this, but it at least remains a plausible explanation. After all, we humans can't compute any non-computable function, or at least none that we know of (the Church-Turing thesis).