Whether it was Adam or any other Phantom, Phantoms were obligated to help each other in difficult situations. Sure, some might refuse like Iren since no one could force them to, but most Phantoms were willing to help any fellow Phantom in trouble.
Fred, Ester, and Romeo were here, and for the same reason, a few other K1-Squads that were near Iron Beacon or in the nearby ruins of Salt Village were on their way.
However... In especially dangerous situations, when a strong monster or aggressive Phantoms from the Lower Ring appeared, the Citadel would send help directly from the center. It was always a stronger Phantom.
Sometimes, it could even be someone like Damien, one of the Second Rank Phantoms, but it happened more on his whim, and only if the mission could be finished quickly, so he would not waste his valuable time.