You can hardly blame the ref in this instance. Mignolet played the ball to Lucas who was outside the 18 yard box and never encroached. The Liverpool player inside the box was never involved in the play and indeed was on the other side of the box. And you are wrong, the Leicester player was never in the box when the kick was made.
You're clutching at straws.
This is a moment just after Mignolet kicked the ball:

