Until now, the method I have used for extracting specific parts from an animated GIF was through the use of the Quick selection tool and layer masks. I would select, on a frame by frame basis, the part I want to keep, refine the edges, then apply a layer mask to remove the remainder of the GIF.
So basically turning this:

into this:

However, my current GIF request isn't working out as easily. I am attempting to extract only the character on the right in this GIF:

But the result is not what I was expecting:

I believe it is some kind of issue with the layer masks, but unfortunately I do not know much about layer masks other than using them to hide unwanted parts of images. How should I go about cleanly extracting this part of the gif? Thanks in advance.
So basically turning this:

into this:

However, my current GIF request isn't working out as easily. I am attempting to extract only the character on the right in this GIF:

But the result is not what I was expecting:

I believe it is some kind of issue with the layer masks, but unfortunately I do not know much about layer masks other than using them to hide unwanted parts of images. How should I go about cleanly extracting this part of the gif? Thanks in advance.