Why was my answer for 00527 get wrong?

[adoin]

type AppendToObject<T extends Object, U extends PropertyKey, V> = T & {
  [k in U]: V
}

Then I can using

const tt: AppendToObject<test1, 'home', boolean> = {
  key: 'cat',
  value: 'green',
  home: true,
}

But all equals shows false. Why?
Why was it must be ```
type AppendToObject<T extends Object, U extends PropertyKey, V> = {
[k in (keyof T | U)]: k extends keyof T ? T[k] : V
}