Instagram's “Watched the reel you sent” notification is now rolling out for Android users
Test by: https://twitter.com/WFBrother/status/1518921745398657024?t=_0Rxs3xZxSSYMmGwZf4Ytg&s=19
As you can see in this screenshots a user can see the message like draft but this is "Watced the reel you sent"
So you know a receiver of reel can Watched the reel so sender of reel will be able to see "Watched the reel you sent"