Current cats terrified of new cat

I have two cats, brother & sister orange tabbies, about two years old that I adopted as kittens.  They are very good cats – affectionate, happy and friendly to other humans.

Enter Max, the black cat:  After three years separated, my wife moved back in last year along with Max. We raised Max from a kitten over eight years ago. He’s extremely affectionate with us, but skittish around other humans.

Max is like a Disney story. A few years ago he got lost in northern California. While lost he crossed two interstates and survived eight months in a state park until the park ranger finally earned his trust, found his chip and got us reunited. He’s obviously a tough little guy.

The problem: My cats (Dexter & Stella) are terrified of Max. At first, last year, Max was aggressive with them, but now it appears he just wants to buddy up so we can all sleep in the same bed together. Max chases them sometimes, but I haven’t seen him attack. If cornered, Dex & Stel hiss and growl, and sometimes reflexively poop. When Max is upstairs my cats run to the top of the refrigerator. But, when Max is downstairs, or appears to be gone, Dex & Stel are back to normal as if nothing ever changed.

Does anyone have a suggestion how to get cat harmony here? We thought about locking all of them together in a room for a while, forcing Dex & Stel to accept Max. But I’m not sure that’s a good idea.  Please help!

Signed,

-Cat Baffled

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