Here is the scenario:
Three players are in offside position and run towards the ball, drawing defenders as they go. In the meantime, a fourth attacker runs from an onside position onto the ball and scores with it.
Are we to disallow the goal because the three players distracted their opponents? If so, how does this reconcile with the guidance that “a player in an offside position may be penalized before playing or touching the ball if, in the opinion of the referee, no other teammate in an onside position has the opportunity to play the ball.”
USSF answer (November 20, 2007):
It is now an established principle that in situations where an attacker is coming from an onside position and another attacker coming from an offside position, each with an equally credible chance of getting to the ball, it is imperative that officials withhold a decision until either it becomes clear which attacker will get to the ball first (even if this means having to wait until one or the other player actually touches the ball) or the action of the attacker coming from the offside position causes one or more opponents to be deceived or distracted.
From from your description, it is possible that the three attackers, by drawing defenders away from play elsewhere, have interfered with their opponents. The referee in this situation must decide whether in fact that actually occurred. Did these three attackers prevent an opponent from playing or being able to play the ball by clearly obstructing the opponent’s line of vision or movement, or by a gesture or movement which in the opinion of the referee deceives or distracts an opponent. If so, the correct call is offside. If not, then there is no offense.
The confusion here appears to lie in the “exclusivity” of the guidance you cite. That guidance refers only to the issue of whether an attacker is interfering with play. In other words, suggesting the need to wait for a decision when an onside attacker and an offside attacker are both making a play for the ball is related to whether one or the other of the attackers will interfere with play. If, apart from this, one or more attackers who are in offside positions are interfering with an opponent, this presents a separate issue.