Allowing signed forms to be included (concatenated) in new PDF's

We have a need to include previously signed forms within an application package that we send to the client. The request is to have a way to insert these signed documents into another PDF. When attempting to do so in Adobe Pro we are advised that the PDF is password protected. When trying to find alternate solutions such as PDF printers to print a flattened PDF we are getting errors. We noticed that PDF assembly permissions are disabled. We do document generation with HP Exstream and would like to assemble the larger document there which limits the custom solutioning for high volume processes. The business area would be ready to assume the risk of loosing the 'digital seal' on the document if the electronic signatures were still 'Active' and verifiable rather than flattened and appearing as regular stamped annotations. Any thoughts on workarounds?