Can I somehow obtain reference to SkeletonAnimation inside SpineEvent callback?

void Start() {
    foreach (SkeletonAnimation skeletonAnim in skeletons) {
        skeletonAnim.state.Event += OnSpineEvent;
    }
}

void OnSpineEvent(TrackEntry te, Spine.Event e) {
    // here I need reference to distinguish which skeleton animation rises event
}

Background: I have 4 characters each of them can cast spells. But spells are not cast immediately, but with some charge animation first. Then this animation rises event "spell_cast" and only then spell will be actually invoked. The problem: I do not know which player has cast spell in the time of handling event. Can I obtain this information in callback. Or at least can I pass it to animation first like index just to get same index back in event? Or any other solution?

The only idea I have now just to use 4 predefinened callbacks with only difference player index. But it is pretty boilerplate solution. Do I have a better option then:

void Start() {
    skeletons[0].state.Event += OnSpineEvent1;
    skeletons[1].state.Event += OnSpineEvent2;
    skeletons[2].state.Event += OnSpineEvent3;
    skeletons[3].state.Event += OnSpineEvent4;
}

void OnSpineEventSkeleton0(TrackEntry te, Spine.Event e) => OnSpineEvent(0, te, e);
void OnSpineEventSkeleton1(TrackEntry te, Spine.Event e) => OnSpineEvent(1, te, e);
void OnSpineEventSkeleton2(TrackEntry te, Spine.Event e) => OnSpineEvent(2, te, e);
void OnSpineEventSkeleton3(TrackEntry te, Spine.Event e) => OnSpineEvent(3, te, e);

This will do the job of course, but is pretty ugly. And (theoretically) if I would need n-sized list with unknown size this will not work at all. The best for me would be just something like:

void OnSpineEvent(TrackEntry te, Spine.Event e) {
    SkeletonAnimation invoker = te.state.SkeletonAnimation; // but I can not find link to it in TrackEntry or Spine.Event.
}