I believe the documents you are referring to are KK’s statements that PF told her KB had abused the baby, and gave examples, which KK did not think were plausable. KK did not believe PF, per her testimony, under oath.
The only verified report to CPS was made by a nurse after the birth of the baby, and were concerns about PF and his conduct at the hospital. The current news reports are speculation (sensationalizing, IMHO) about what is in the DHS report.
DHS’s reports and court hearings are generally not open to the public. Keeping the records sealed would follow normal guidelines regarding proceedings, findings, and witnesses.
I believe we can assume, since no criminal charges were filed, and custody was not taken away from KB, that all concerns regarding the parenting abilities of KB were unfounded. We do not, however, know if any restrictions, anger management, parenting classes, supervised visitation, etc. were ordered for PF or KB, because these would be sealed.