Investigation
Usually, forensic investigators need at least a week to conclusively determine whose remains were identified and where or what they came from. They had stopped John from making the call because what they had discovered indicated that this case would not require further investigation. They already had everything they wanted.
False Alarm
They saw the skeleton of a life-size human, but it was also a fake one. Someone must have planted it as a Halloween scare or joke inside the tree bark and forgot about it. They laugh in relief, but what they can’t understand is why Kyle would warn them about a situation like this.