This is the time where you ask whichever fsdo guy that you happen to talk to, "Are you the real FAA or is the Houston guy the real FAA?" Personally, whenever I've been ramp checked, I've never been asked to see my endorsements. I don't carry my logbook when I fly, so even if they wanted to see them, they wouldn't be able to. Even if they did see the endorsement, that would probably be the end of it. I can't imagine that they would continue on trying to figure out how you got the endorsement unless you had an accident or incident involving knowledge you should have gained from the endorsement process. Long story short: Get the endorsement and don't worry about it.