Song of Sarkoris and Paired Opportunist

[Wonderstell]

Song of Sarkoris:

When you complete the performance, all allies within 30 feet gain an attack of opportunity when reduced to negative hit points, or whenever a foe deals hit point damage equal to or greater than its Hit Dice, for the duration of the performance. The attack of opportunity can be made against any enemy within reach; it does not have to be against the source of the damage, and does not count toward your allies’ maximum attacks of opportunity per round. This attack of opportunity is resolved prior to the enemy’s attack, but the triggering attack is still resolved even if the enemy is killed or incapacitated.
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Paired Opportunists:

Whenever you are adjacent to an ally who also has this feat, you receive a +4 circumstance bonus on attacks of opportunity against creatures that you both threaten. Enemies that provoke attacks of opportunity from your ally also provoke attacks of opportunity from you so long as you threaten them (even if the situation or an ability would normally deny you the attack of opportunity). This does not allow you to take more than one attack of opportunity against a creature for a given action.
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Would the AoO-sharing effect of Paired Opportunists interact with the AoO from Song of Sarkoris?

Paired Opportunists requires an enemy to provoke an attack of opportunity to trigger, and there's no such language in Song of Sarkoris. Normally I'd not spend much time overthinking this but since you can make the AoO against any enemy, not just the one who made it happen, the answer to "who provoked it" is not obvious.

[Zog of Deadwood]

Normally an AoO can only be made against the opponent who made it possible (provoked it), but although Song of Sarkoris specifically makes an exception to this general rule the only other difference to the usual AoO mechanism itself is that any AoO(s) thus generated cannot prevent the completion of the action that provoked them. So a paladin ally could take a massive hit from an ogre that would kill her, all party members (including the walking dead woman) would get an AoO against whoever they felt like attacking, but the pally would still die, even if every party member's AoO hit and the entire ogre murder-family also went down.

There would be nothing in that scenario that would have any bearing on the fact that it was the action of the ogre matriarch successfully gutting the pally like a trout that generated all those AoOs in the first place. I don't see how the target of the AoO has any bearing in this case on the question of who generated it. That being the case, since "provoke" has no alternative meaning within the ruleset outside Attacks of Opportunity and merely acts there as a synonym for "gives rise to" or "creates the opportunity for", I don't see the loss of the word as important. Given the differences between the AoO granted by Song of Sarkoris and the ones the rules generally allow for, it would have been far easier for them to avoid calling it an attack of opportunity at all if they did not want it to interact with the AoO rules and feats. Song of Sarkoris could have simply granted a single extra out of turn attack that was resolved simultaneously with the attack that generated it. They didn't do that. Paired Opportunists should absolutely apply.

[Scott Wilhelm]

Well, "provoke" just means give rise to or cause to happen. I'm sure the Song of Sarkoris Attacks of Opportunity are provoked for the purposes of Paired Opportunist'.

But I have a problem with Song of Sarkoris itself. It says it takes effect "when you complete the performance." But allies gain their Attacks of Opportunity "for the duration of the performance." How can you use a dweomer that only effects things while it's going on but doesn't take effect until after it's not going on anymore?

I guess they intended to say "when you activate the performance" after the Full Round Activation time, but I recommend PC's not take this Masterpiece unless you have some kind of time-travelling masterpiece.

[Wonderstell]

Thanks for the insight. Sounds like I was just overthinking it.

A hypothetical scenario I had in mind is that an enlarged reach weapon Fighter stands 20 ft away from a dinosaur engaged in melee with their Monk ally, and this Fighter gets shot by another enemy from far away. The ranged attack deals enough damage to trigger Song of Sarkoris, which means the reach weapon user can attack the dinosaur with the AoO.
In this situation the far away ranged enemy is the one who 'provoked' the AoO in the technical sense, which is why I hesitated on Paired Opportunists allowing the Monk to also attack the dinosaur.