Just a questions to make us think but what is considered initiating contact? The two R players that got blocked on the second KO both ran forward towards the K players and then the contact occurred. Who initiated it? I have always thought of the not initiating contact as the player standing there waiting for the ball to get there or going after the ball and getting blocked more like the first KO even though it appears that the ball had gone 10 yards before the contact was made.
You can see the two R players start towards the ball then stop when they realize they're about to get clobbered. On a play like this where the K players are actually ahead of the ball it's obvious that their intent is to initiate contact.
But just as a general rule, I would say that an R player coming across their restraining line near the ball is going for the ball unless you're 110% that they're looking for contact. However, bracing for contact to defend themselves when they see a K player approaching isn't initiating by R; R needs to be actively seeking the contact. If an R player comes across their restraining line and the ball is not in the area then they're obviously looking to initiate contact.
To really simplify, I think a good rule of thumb is:
As the ball is kicked, R remains focused on the ball while coming forward: R isn't initiating contact.
As the ball is kicked, R shifts his focus to a K player while coming forward: R is initiating contact.