Her combativeness on the stand is clear indication of someone who has either been in the juvenile detention system or still is. She knows how to answer questions in an unresponsive way.
Worked for awhile with our local juvenile center. She may have been allowed to speak with her “officer” Which would have explained her change the second day. Am betting you are right and she is still in the program. It would explain a lot We don’t know what is in her probation requirements.