Every once in a while you find yourself with a blend file, that clearly has animations, but the animations aren't showing when you scrub through the timeline, you know that they exist because you can see them when you start up the internal game engine, so where are those actions hidden? Well I recently experienced this, and it took a while, but I found the animations, so I thought I would share my discovery in the hopes that this post could help somebody else out at some point.
Firstly you need to change a panel to the dope sheet view. It's probably easiest if you just change to the default animation layout and then proceed from there, as everything will be set the way you need it.
Make sure you are viewing the Action Editor, and that you have the object that has the animation selected, in most cases it will be the armature.
Click on the little button that the arrow is pointing to and you'll get a little menu that opens with all the actions that the object has, select any one of those to temporarily bring it into the timeline, you'll be able to scrub through and see the animation, and if you change back to the normal dope sheet view you'll be able to edit and make changes to the animation. But in this case I wanted to have about four of these actions all in the timeline so I could export the model with those animations to use in Minetest.
After selecting an animation you'll see all the bones that have animations showing, and the individual keyframes that they have for the animation. If you want to use the animation in the timeline with several other animations click on the Stash button, it's circled in the image, you may have to scroll on the menu bar as it could possibly be off the visible portion of the screen, depending on your screens resolution and the exact layout you are using.
After you've stashed all the animations you want to use you'll need to change from the dope sheet editor screen to the NLA action editor screen, as show in the picture below.
Your stashed animations will be muted and locked by default, just click on the little lock and speaker icon to unlock and unmute, and then you can arrange the strips in whatever order you want, and when you scrub through the timeline you'll see all the animations.
That's it, hopefully this was clear and easy to follow, if it wasn't, feel free to leave a comment and I'll try to improve it for you.