If you pick at any scab long enough, you can make it bleed. The 1st exception to a defensive player for "Roughing/Runnining Into the Kicker (NF:9.4.5) is: (a) Contact is unavoidable because it is not reasonably certain that a kick will be made. For better, or worse, this involves a judgment call that is unique to each and every incident.
To avoid violating the rule, the contact must be "unavoidable", for which there is no NFHS definition. A dictionary definition is, :"than cannot be avoided; inevitable", and is further described by "not reasonably certain that a kick will be made", that lack of certainty lends itself more to a rugby style kick, than a standard punt, and usually provides extended leeway. However, the ultimate judgment is based on the sole perspective of the Referee, who one must presume considered both factors before rendering judgment.
NF:2.32.8, specifically defines when a player becomes a kicker and when how long he continues to be a "kicker". Any contact, during that interval, judged to be illegal would be appropriately Roughing/Running into the kicker. That player, prior to becomming a kicker, or after ceasing to be a kicker, would be protected by any of the rules governing other players.
The running (rugby style) kick only adds to the difficulty of this judgement. Ralph provided a logical and rational perspective to assist in arriving at the proper judgment, but each judgment that is made will be unique based on what is specifically observed. You should be warned, and aware, that universal agreement with whatever judgment is ultimately rendered is exceptionally rare.