see e.g. Wahbeh, H., Radin, D., Cannard, C., & Delorme, A. (2022). What if consciousness is not an emergent property of the brain? Observational and empirical challenges to materialistic models. Frontiers in psychology, 13, 955594. https://doi.org/10.3389/fpsyg.2022.955594
https://en.wikipedia.org/wiki/Hard_problem_of_consciousness
Same for memory, which is "needed" as well for your question to make sense. The more current theories assume memories are stored not only in the brain, but throughout the body.
see e.g. Repetto, C., & Riva, G. (2023). The neuroscience of body memory: Recent findings and conceptual advances. EXCLI journal, 22, 191–206. https://doi.org/10.17179/excli2023-5877
No it's not, not by anyone serious.
We know the brain is the seat of consciousness because damage to the brain damages consciousness. There is no other organ in the body where that's true. You can completely replace all other organs without changing consciousness.
You can always find a paper by a quack that posits the earth is flat, that doesn't mean there's serious debate.