If you can stop them from taking the throw, you can move it to the right location. Even if you whistle for them to stop and they throw it anyway, you can move original team's throw to the correct location and have them try it correctly. I suppose you could also invent a reason that you didn't indicate they could proceed, and have them try again from the right place. Anyway, if it didn't matter then it's trifling and doesn't need to be called.
I’ve done it. But that was after I had already moved the thrower back 10 yards from where he wanted to take it. Then he proceeded to run to the exact spot I moved him back from and throw the ball.