This is a normal dropbox link :
https://www.dropbox.com/s/7wy52jbqtxkr5cl/Recording%20%237.mp4?dl=0
This is a embedable dropbox link : https://www.dropbox.com/s/7wy52jbqtxkr5cl/Recording%20%237.mp4?raw=1
To make it embedable you have to change the id=0 to raw=1, however while most forums have the abilty to embed dropbox links, itch.io does not.