Unless you somehow reverse engineer I suspect most all of the information needed is confidential restricted to HPE and select Zigbee partners constrained by nondisclosure agreements.
Coming in late. I am able to track BLE beacons and also extract temperature/humidity data from Govee BLE sensors. Basically, I use an IoT transport profile with websocket enabled, A simple websocket server in Python receives the data and pass it to home assistant through mqtt. I happen to be an Aruba engineer, but I didn’t need any non-public documentation. I am not a programmer, not enough time and qualifications to write a proper integration.
I just wrote a little example to parse the Xiaomi Mija BLE sensor, seems to be working just fine with 5 APs and 6 Xiaomi Mija sensors. Sadly I had not enough time to write a full integration, but maybe this still helps some people.