I just want to take a number of pdf documents that have been digitally signed by others, who sent them to me, and combine them in an omnibus document that will bear my digital signature.
Let me explain the purpose by analogy. It's like a firm's report that certifies the separate property inventory reports that have been separately certified by independent department heads. It must be a very generic business requirement.
The basic premise of my requirement is that I have to accept unstructured digitally-signed pdfs received by others - I have no control over a master template that everyone must use.