It's not clear how you rendered the video, since the blend file you have provided is set to render as separate
png still frames:
Rendering it with the Animation button (or CtrlF12) works fine on my computer so I can't reproduce your issue and I believe it might be related to the extra steps you took to actually make the video.
I suggest you keep rendering as still frames (like in the file you uploaded), but to change first the "Output" directory to something which is not a temporary one.
After it has been rendered, check that your output frames look good, and finally merge them into a video (you can do it with external applications, or within blender following steps 3 to 6 from this answer: https://blender.stackexchange.com/a/15145)