How do I play a timeline from a timeline and then override its animation using some avatar mask?

I am trying to make a “conversation” timeline where one guy is sitting on a chair and chatting to himself. “Sitting” is a timeline that contains information such as where the chair is, how fast to play the animations, etc. I play it with Control Track and it plays fine. However, what I also need is to play some “chatting” animation as an override on top of the sitting animation. I tried to use Animation Override Track, but it does not work. The “sitting” timeline plays fine, but the “chatting” animation is ignored.

I assume it’s because the “sitting” timeline is overriding any animations that the “conversation” timeline has. And if I put the “chatting” animation in the “sitting” timeline, then everything works great. However, I really need the “chatting” override animation to be in the “conversation” timeline. I need to be able to combine timelines in a master timeline and spice it up with various additional animations.

So what can I do? I am a beginner with playable graphs and I really don’t understand how they are structured, but I assume that I could manually create an override animation playable and add it to the current top animation graph to make sure that it will play. Does this sound like a good idea? How would I do it?

You can place them in different timelines on different animation tracks, but in editor preview, only the preview from one track will be applied. In playmode however they should both play and blend together (if your clips ease in/out).

Does not seem to work for me in play mode or otherwise. Here is my setup:

6622630--754555--upload_2020-12-15_11-20-3.png
This is the master timeline.
6622630--754558--upload_2020-12-15_11-20-32.png
This is secondary timeline (Test Timeline 2) that is being played by master timeline .
When I play this, the BardicheDialog1 is just getting ignored. However, if I setup something like this:
6622630--754561--upload_2020-12-15_11-23-9.png
Then the BardicheDialog1 is being played fine.
This is all in play mode. What am I missing?