Are there any randomized controlled trials that show this? (As opposed to no-randomized observational studies)

That's not true. The WHO thinks red meat might be a carcinogen. From the Q&A mentioned in your first link [0]. Also, I would not consider your second link a reliable source. An animal-rights group is not unbiased.

> In the case of red meat, the classification is based on limited evidence from epidemiological studies showing positive associations between eating red meat and developing colorectal cancer as well as strong mechanistic evidence.

> Limited evidence means that a positive association has been observed between exposure to the agent and cancer but that other explanations for the observations (technically termed chance, bias, or confounding) could not be ruled out.

[0] https://www.iarc.who.int/wp-content/uploads/2018/11/Monograp...

My suspicion is that it's the sodium nitrates used in treating certain meats that's causing a lot of the cancer. But this is just speculation on my end.

Did you miss the last few years? The WHO is not to be referenced