Then provide an alternative theory. The world would love to know where this virus came from, and how it mutated to what it is.

Our best guess is that SARS originated from bats and jumped to humans via masked palm civets, which are typically sold in live animal markets in China. This is not just my own pet theory, you can read the extensive literature on the topic.

This is an already known and suspected theory. But there is no evidence that it came from eating it.

Then explain how MERS appeared. Did people of the Middle East suddenly have a gourmet taste for eating camels one day?

Camel meat has always been popular in the Middle East. About 3M camels are slaughtered for meat every year. It's similar to beef, and considered a halal meat for Muslims.

Isn’t the meat cooked? That normally kills off germs and pathogens.

What's your point? Most people cook their meat before eating whether it's camels, bats, or civet cats. The serious cross-species disease transmission risk is from unsanitary practices in handling live animals and raw meat before cooking.

Fully killing off viruses would require bringing the internal temperature of the meat to around 70 degrees C. People do not typically do this for red meat as the resulting texture is unappealing.

I don’t think anybody said that somebody ate a civet and got sick. However, civets are not naturally to be found in close proximity to humans. The jump from species to species was due to the appetite for civets causing them to be held in cages at wet markets for prolonged periods of time.