Chat mode does not support passing video, a link always has to be sent,
Your wife's phone is doing it for her.
Video contains a humongous amount of data, and that requires a lot of time to send back and forth.
For me, just to upload a video to YouTube takes almost 90 minutes for a little tiny 5 minute video.
That is because my upload link speed is restricted by my ISP to about 500 kbps.