His thought problems with evil surgeons and logic paths from photo-receptor to color qualia are not actually arguments, they are efforts to guide his reader's intuition to make his particular worldview more intellectually satisfying to them. They are perfectly acceptable persuasive tools, which is as closclose as it comes to saying "yes, they are as valid as any other persuasion is."
Dennett himself, in one section of Consciousness Explained, also had to address the way our minds act as von-Neuman/Turing machines, despite being wired completely differently. Our brains are wired a massively parallel neural nets, with no central processor unit, no linear processing etc. Our computers are designed like we reason, as linear von Neuman machines. Our brains are instead wired in a parallel analog fashion. ToTo address this tremendous disconnect between wringwiring and brain function, Dennett postulates that we "run a virtual Von-Neumann machine on our analog hardware". But running programs and having virtual machines in our heads -- is not DISPOSITONS (analog neural nets DO develop dispositions), and. It is instead pretty explicitly "theory of mind" "in our heads" being "causal", and Dennett admitting all of this to be “virtual” is Dennett himself adopting a causal dualism that he repeatedly savages among his peers.
So, between his peers being convinced by the experience of experience, the utility of theory of mind, the advances in science demonstrating the reality and causal nature of both qualia and consciousness, and Dennett himself not even being able to build a behaviorist model and having to resort to an emergent causal dualism -- Dennett's persuasive advocacy -- has run into a suitemultitude of falsifying test cases.