School Staff Discussing My Daughter Negatively In Front Of Other Students

My daughter (I'll refer to as "M") is a high school senior. She has had a really rough 2 years with mental health struggles and substance abuse. This has taken a huge toll on our family, I have done so much to help her. Life at home has been a roller coaster and school has been horrible. M hates school and does not respect staff and has gotten in a lot of trouble. I have a great rapport with the principals, they know I try so hard with M and they actually sympathize with her as they know M is capable of being a great kid but she has these struggles. M has spent a ton of time with this one school pyschologist I'll refer to as "C" and then there's her guidance counselor I'll call him "L".

Last week M's friend told her that she was in the area of the counselor's offices and overheard C & L and another staff member talking about M. C was telling them about M giving a teacher an attitude and the convo was kind of like "Who does M think she is talking to teacher like that? Teacher is pulling in 6 figures and she goes home and rests her pretty little head on her pillow happy as can be and M is sitting home with no diploma and she needs to be put in her place". The gist of the convo I agree with. M is disrespectful and this is a huge issue for me and my husband. But then some of the convo was L asking C if M has some kind of trauma in her life and C's response was like "What the hell trauma does she have?" and then said M is "Impossible AF" and then said "She's literally evil". Saying M needs to be psychologically evaluated. C then is saying she needs to show up, shut up and graduate to which everyone around was laughing and talking about how funny they thought that was. C told everyone that M is non compliant with her antidepressants. Forgot a key detail......M's friend recorded all this on her phone. So there's no disputing that these things were said. There was more but hard to hear some of it. This convo went on about 10 minutes. My daughter has been extremely close to the psychologist "C" and this woman has been amazing the past 2 years. She's helped M through some horrible times. Graduating was going to be so hard for M with leaving C and losing that connection. M is devastated and embarassed to hear how they were talking about her. I was livid listening to the audio and started an email to C & L to basically say that what they said was recorded and how hurtful it was to M. Before I got a chance to send anything I got a call from the principal saying he was just made aware of the situation and this is being taken very seriously and apologizing. M had a meeting with principal and they asked her what she would like to see happens and whatever.

I'm not sure what my daughter and I should be doing on our end. I don't like that the school's attitude is like "We'll handle it from here" and have kind of already said it'll be handled privately within the school and that we won't know what is being done as it's now a school matter. The 3 staff members were talking so negatively about M (calling her evil!!!), discussing medication, questioning trauma, etc not only around other staff but students. This is horribly unethical. Humiliating for my daughter.

Location: Illinois