misunderstanding timeline animation tracks?

Hello, I have 3 characters (with Animators) that I want to play the same sequence of anims on simultaneously. I created a Timeline with 3 animation tracks that have identical anims on them. I assigned a different character's Animator to each track (see image).

The problem is that when I scrub the preview or in Run mode only the first (top) character plays, not the other two. What am I not understanding or doing wrong? Thank you!

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