Hello, unfortunately I'm not familiar enough with your workflow to spot the issues, but it would probably help if you zipped your project file and uploaded that to google drive for people to take a look at. I do have some suggestions though.
Instead of using "Play Animation," I would look into using the animator and the "Animator Play" action. The animator (mecanim) is very easy to use with a bit of practice, and you'll be able to see the flow of your animation that way, so debugging will be much easier.
For your issue with the Global Variable not showing up in certain FSM's, I'm not sure about that either; however, I would recommend not using Global Variables at all. Instead, I would use a game object with the variables you need, and then use "Get/Set FSM [Variable]" actions to accomplish the same thing. I've experienced bugs with Global Variables in the past, and I've found that they're not necessary. Just attach an FSM with "Don't Destroy on Load" to the game object with the variables, and you can access them from any scene.
Sorry for not having any solutions, and good luck with your project.