Hopefully this is it. However, you will have to do this every time you try to share a video with non-iOS users. Also, I didn’t try sending videos to iPhone users while in this setting, because it was just to late at night when I figured it out.
I noticed that when you disable iMessage, MMS stays on for some reason. You need to disable that too (again). So follow these steps:
- Settings / Messages / Turn off iMessage.
- MMS will stay on, so go ahead and disable it.
- After you send your video turn iMessage back on. *
* I did notice that when you turn iMessage back on, you won’t see SMS back on also right away. It takes a few seconds to bring it up.
Try sending videos to iPhone users using the iMessage and MMS off settings and let me know if if works.