V20 has a possible answer to this problem on page 276:

Multiple Opponents: A character who battles multiple opponents in close combat suffers attack and defense difficulties of +1, cumulative, for each opponent after the first (to a maximum of +4).

So, if you engage the target enemy in combat all at once, you will help all of your friends who are also fighting him by making it a lot easier for them to hit him and defend from his blows. If all of you attack him at once, he will face maximum difficulty (10) for all of his combat rolls, making it extremely hard to score any successes. However, as far as I know it, nWoD uses constant difficulty instead of variable, so it will not be easily transferable over there.

What you can also do is performing other combat maneuvers listed on pages 276-278, some of them do not deal direct damage to the enemy, but rather make it easier for others to attack him. Even though those maneuvers actually need some combat skills to be present, you still have a small chance to perform them successfully, and this chance is probably bigger than successfully dealing damage to a combat character as a non-combat one. And, moreover, even trying to perform them counts as being in combat with the enemy, thus applying penalties to the latter.

Hope that it helps.

V20 has a possible answer to this problem on page 276:

Multiple Opponents: A character who battles multiple opponents in close combat suffers attack and defense difficulties of +1, cumulative, for each opponent after the first (to a maximum of +4).

So, if you engage the target enemy in combat all at once, you will help all of your friends who are also fighting him by making it a lot easier for them to hit him and defend from his blows. If all of you attack him at once, he will face maximum difficulty (10) for all of his combat rolls, making it extremely hard to score any successes. However, as far as I know it, nWoD uses constant difficulty instead of variable, so it will not be easily transferable over there.

What you can also do is performing other combat maneuvers listed on pages 276-278, some of them do not deal direct damage to the enemy, but rather make it easier for others to attack him. Even though those maneuvers actually need some combat skills to be present, you still have a small chance to perform them successfully in any case, and this chance is probably bigger than successfully dealing damage to a combat character as a non-combat one. Moreover, even trying to perform them counts as being in combat with the enemy, thus applying penalties to the latter.

Hope that it helps.