I had no problems recording and the district recorded as well so we both have a recording. I will say that my recorded did not pick up everything because some people speak softer than others. I also had to record offline because our school is a bunker. that said in the future I have picked up a conference room microphone to plug in to pick up everything when I record for future meetings. And the Otter AI app I used did a decent job of transcribing and the summarizing information. so I was able to send a follow up email with bhours of the meeting. I am hopoing that in the future that the app will voice recognition so that each person can introduce themself when recording starts. etc. I know with zoom etc. it does keep track of that stuff.
I don't understand this "scheduling" or "calling for" a due process hearing. Did you receive any paperwork on this? The paperwork should explain why the school district is filing for due process, give you a deadline for your response, etc. It sounds like you've had an attorney before. I would consult with him/her on this matter.