The article you linked does not talk about missing primates. They were doing experiments on monkeys. Activist put pressure on them to stop and they did stop. Then they rehomed the monkeys to a sanctuary.
They are “missing” in as much as the monkeys are no longer there, but everyone knows where the monkeys have gone and why the monkeys have gone. The article you linked itself explains this.
The article you linked does not talk about missing primates. They were doing experiments on monkeys. Activist put pressure on them to stop and they did stop. Then they rehomed the monkeys to a sanctuary.
They are “missing” in as much as the monkeys are no longer there, but everyone knows where the monkeys have gone and why the monkeys have gone. The article you linked itself explains this.