Ok, caught up. You're never going to find a way to have this all connected into a single path, except by having some parts overlapped. I'll try to make an illustration in a minute. But the reason it won't work, is because a node can have either 1 path emanating from it, or 2. 1 or 2, no more and no less. For example, where one end of one line segment of the X touches the circle, 3 different segments theoretically would meet there. But you can't do that with Inkscape, and have only one node at the place where they meet.
Here's what I had in mind, and what I thought you were asking. Follow the numbers for the order of node placement.
I thought you had already placed nodes 1 through 8, and that you just needed to place node 9 back at the starting place, to have the fill completely inside the circle.
Oh, btw, do I understand that you've now figured out how to break the ellipse apart? May I please suggest that when you have questions, you first try and find the answer yourself, before posting a message asking how to do something?
I hope you've learned through this little ill-fated topic, that there are many ways to make a circle with an X. No one way is any more proper than the other. It's just whatever will work in your current image's circumstances, and your own preferences. There are some fairly uncommon situations where there might be only 1 or 2 ways to do a certain task. But with Inkscape, there are often at least a few ways. Learning what works best in which situations, and according to your preferences, is how your own skills are developed