D3 players can get cut for any reason, at any time. D3 coaches we met with during the recruiting process often offered some variation of “I’m offering you a spot on the team for your first year. After that, it’s up to you what happens. If you contribute, you keep your spot.” We know kids at a number of schools who lost roster spot for injuries, after better players in their position were recruited in after them, disciplinary problems etc.
As others suggested, encourage the student to request a meeting with new Coach and Assistant, particularly if the Assistants haven’t changed, to discuss roster plans.