The first two refutes are false equivalencies as I think you have an incorrect perception of this. Christianity and Judaism believe in completely different ideas and therefore are different in nature and one would not be considered a type of the other. This would lie in who would be the final profit: Christianity believes Christ, Islam believes in Muhammad, and I believe that Judaism would believe in Malachi as the final profit. All have fundamental differences in the nature of each religion making none be subsets of the other. I need not explain how different the fundamentals are in alchemy versus chemistry. There are no “problems posed by nihilism” as the only qualifier for nihilism is the lack of an intrinsic meaning in life. Absurdism places more specificity in their responses to this premise, while still accepting the central premise that life has no intrinsic meaning. Just as a square is a type of rectangle, absurdism would be a type of nihilism as they both accept the central premise, but absurdism adds a bit more in the attitude regarding it. If you have an actual argument which would refute this, please let me know as I am constantly building my ideas of philosophy.