Legal Question in Real Estate Law in California

Not unless the Operating Agreement of the LLC says they can. A properly drafted LLC Operating Agreement, however, would preclude the charity, or anyone other than the original members for that matter, from becoming members or otherwise exercising ANY control without the approval of the remaining members. A good LLC OA has thorough provisions for restricting successors to the economic interests of members from becoming actual members without approval. If your OA does not have such provisions and no one has died yet you REALLY need to get to a good attorney and amend your OA.