In Ohio, How do title companies confirm the authority of the Trustee of a mortgage backed securities trust to convey property they purchased at Sheriff's Sale after Foreclosure?

I am looking at a deed from XX Bank as Trustee of XX co. Series 2001-AMI. How do I confirm that XX Bank had the authority as Trustee to sell this property?

There is no Memorandum of Trust filed in the county records and no Affidavit to support Trustees authority. AND XX Bank refuses to provide a memorandum to my client.