Allowing an impartial Station to intervene before a rift opened between the most important people in Buckle was right. Logically, Chain knew she should let Grain dig through the records for inconsistencies. It would be sensible and politically-sound to carry on her normal patrols and day-to-day activities.
But as the days passed, as she went to visit parents concerned with the behaviour of their teenagers, or checked on the most poorly-built homes, the idea that someone skimmed from the Family Mine became a sore tooth: it throbbed, it ached, it would not be ignored. Her instincts repeatedly told her not to leave matters to Grain. With each hour spent on her duties, it became more and more impossible to ignore a compulsion that could only have come from Sol.
The next morning, she knew she couldn't leave the investigation alone. It was divine inspiration. Chain decided to at least speak to Side, ensure she'd not missed any details that might press Grain into faster action.