no.... that only sound like you know legal talk. I no think you are legal fellow lawyer person. that not at all what "due diligence" is used to mean. you are more like doing do-do dillygence. Or Shilli-gence.
if you lawyering person, you tell us who you are? OK? If lawyer, you have no fear, right? then we check you for truths.
STOP !! The Original Poster merely asked for information, and made no allegations of impropriety by the caller. Subsequent posts have not given the information asked for, so this thread should be silent once again.
Please read the 4 bullet points below that introduction on the first page of the site. All 4 talk about sharing information about unknown callers, with an emphasis on telephone sales pests and scammers.
You still haven't told us how you found this site. When I google my accountant's phone number this site does not appear on the first page of results.