Can the trustee of a will give items of the estate to non beneficiaries and refuse an interim distribution to the stated beneficiaries?

The trustee under a will MUST distribute the estate according to the provisions in the will. The trustee does NOT have the authority to make gifts to non-beneficiaries unless that power was granted in the testamentary trust. The trustee should be reported to the court that appointed her/him for mishandling their authority and the estate. You should ask the court to appoint a successor trustee.