Three Possibilities

While Minos was preoccupied with the problems of the Black Plain, the Spiritual Kings sent by the Chambers family to investigate Kevin's death were investigating what had happened.

Three people had previously been sent to the attacked base to increase searches in the region, in partnership with Chad's group. They had waited at that base until yesterday, when Roy finally showed up, arriving at that place after days of fleeing persecution from the Hayes family.

Roy had barely survived the persecution of that group of Spiritual Kings and was seriously injured when he arrived at that post. Even his winged beast was in horrible shape, having arrived at that base completely bruised and soiled with its own blood.

Finally, after reaching a place where he was safe, Roy recounted everything he had been through to the five Spiritual Kings before he was finally released to receive his treatment.