The Ageless Ones were Temporal Operatives who were trapped in the past when their experimental prototype “time drive” malfunctioned and exploded. The explosion caused a momentary rip in space-time and sent the remains of the ship over 1 billion years in the past. The event destroyed their communications equipment as well as any emergency beacons. Most of the ship’s crew died, leaving just a small handful of about a dozen or so.
Although an Operative is sworn to not interfere with the past, these were special circumstances. One of them was captured while getting food and medical supplies for the small group since they had crashed in a relatively uninhabited area of the mountains. The group knew how far in the past they were and they broke their oaths against interference to save their colleague on the excuse that they were so far into the past it could not possibly matter.