Replay showed James was not in a legal guarding position because he was turning his body and moving into Durant when contact occurred.
Thus the initial call on the floor was overturned and James was assessed a blocking foul.
-From NBA L2M (
http://official.nba.com/wp-content/uploads/sites/4/2018/05/L2M-CLE-GSW-05-31-2018.pdf)
Just admit you're wrong. You're bordering on conspiracy theory level here, lol.