Not arguing, but I’m assuming a license plate registered to MF was the lead, or something else very loose. This was when they said they didn’t know if HB had left of her own will or if there was foul play. When they got an address, they didn’t know what they would find inside. Could’ve been two friends commiserating about rotten boyfriends, or an abduction or multiple homicides. No one knew. They really couldn’t go in with guns blazing, but they knew they potentially might find Heidi and Margot. They might’ve figured the fastest legal way to get access was by asking for a wellness check. Had they entered illegally, whatever evidence they found could be inadmissible (fruit of the poison tree doctrine.). I’m not sure they expected to find what they did. JMO of course.