Downloaded your two RAW files. I brought them into Canon DPP. And I noticed the style is a user specified one, and is CINESTYLE.
So, a style meant for video, and I think sets the aspect ratio to 16:9 instead of 3:2 w/o user intervention. This affects the embedded JPEG and not the RAW. The RAW is still 3:2.
No, aspect ratio is not an attribute of Canon Picture Styles, so Cinestyle does not do that. They are analogous to Adobe raw profiles: Only about color and tone, and not affecting aspect ratio. All Cinestyle does is apply a flat color grade suitable for cinematic color grading.
The other reason is that none of the downloadable examples are 16:9. So obviously Cinestyle did not apply 16:9.
Looking at the downloadable examples, I’m leaning toward the conclusion that this looks like a bug, which might be recoverable with the DNG Recover Edges plug-in if it works, and if not, then hopefully wait for a bug fix.