How to force stitching two RAW files to 360°?

My VIRB 360 camera was crashed during recording. But in my microSD card I found two MP4 files. Both files have the same duration and looks like not corrupted. Why VIRB Edit no detect these as able to stitching? Can I force stitching any two MP4 files in VIRB Edit? ciq.forums.garmin.com/.../1459061.jpg ciq.forums.garmin.com/.../1459062.jpg