Is each organisation's data kept separate in Skie?
Yes. Skie is organised so that each organisation has its own structure, users, devices, policies and records, and roles limit people to the parts of their own organisation they have been given. One customer's administrators do not see another customer's data. Ask for the technical detail in your security review.
Skie is a multi-organisation service. Every customer is an organisation at the top of its own hierarchy, with schools, branches, groups, students and devices below it. Users are invited into an organisation and see only what their role at that level allows.
Policies, app lists and device records follow the same boundary. A school admin works inside their school, a class admin inside their group. Because rules flow down from the organisation and the most specific level applies last, the structure also decides who can change what.
Some things are shared across customers by design and are controlled by Skie, not by you. Examples are the global app catalog and the curated list of DNS filters. An organisation chooses from these. It does not see another organisation's own app store or private records.
Within the Skie team, owners and technicians can reach organisation data for support, as covered in your agreement. Staged rollouts of app updates are chosen by organisation too, and an organisation can be frozen to block new provisioning without touching others.
A practical tip: if your procurement team wants more than a summary, send them a short list of questions about how data is separated, how access is logged and who at Skie can reach it. A written answer is better for your file than a verbal one.