The Vistani are not interested in becoming involved in disputes involving outsiders. When one enters the camp proper, there is a sign that details their stance:
"Do not bring your giorgio business, quarrels and conflict here. This is not a safe ground for outsiders - if someone has a quarrel with you, hide or seek refuge elsewhere."
This is not a statement that they will protect victims or enforce common laws, but one that they will not involve themselves. They will look unkindly on any encounters that trouble them or threaten their families, business, or holdings. It is a complex scenario that is not defined as PvP or not PvP, but one considering the variables of the conflict. The Vistani Captain would not take offense to a slit throat fifteen feet away, but if that same death comes by a fireball, that might threaten him because if the fire spread it could endanger his livelihood. Djordji does not want death in his residence and place of business at all, for example, but the Vistani meandering the camp might only glance if someone is killed outside of their ring of vardos.
The same consideration goes for matters outside of PvP. If your character has an animal companion, summon, or shifted form that is alarming - the Vistani might find objection. If it is a creature that is encountered hostile in the wild or something unnatural, it would illicit a reaction and a DM should be present to support a believable encounter.
The curators of the Keep of the Dyad hold a similar stance to the Vistani. If their people are harmed or threatened, then there is concern, otherwise the sum of conflict in their eyes is merely a mess requiring tending. Fortunately, most assailants have the consideration to clean up the bodies from the scene.