Glenn,
The Protecting Tenants at Foreclosure Act (PTAFA) does not have any implementing regulations or model forms. All we have is the bare bones requirements of the law.
The law does not specify any particular method of notice, but err on the side of caution and provide the notice in every way possible; the expense is negligible. The law does not address whether other notice information may be included in the notice or not. I suggest using one form for the PTAFA notice and include other information, such as the party to whom the payments are now payable, on a separate notice.
You need to consult with your legal counsel regarding issues related to the lack of a rental agreement. If there is no rental agreement the arrangement may not be a bona fide lease or tenancy, and then PTAFA may not apply.