What Does Engineer A Know about Manufacturer Z?
From this description we know nothing of any engineering comptence of Maufacturer Z, much less what knowledge Engineer A had of that competence, if any. Engineers do use computer tools from reliable sources, but we are not given any reason to think the reliability of this tools have been tested. Instead, it appears that Engineer A, perhaps because s/he is acting outside of his/her sphere of comptence, has bought plans of unknown worth and passed them off as his/her own engineering work, which would be clearly irresponsible and a violation of the codes of ethics of several engineering societies.
Engineering Assistance posted by JRattenbury
What Does Engineer A Know about Manufacturer Z? posted by CarolineWhitbeck
Free Software, A Variant of the Engineering Assistance case posted by CarolineWhitbeck