DY, apology accepted. I did not mean to imply that I didn’t hold yom tov sheni, I just didn’t understand why it was extended to visitors to EY where there never was a sfaika. Chazal didn’t set it up this way haphazardly, they had their valid reasons I don’t believe it to be a sign of disrespect or lack of emunah to seek the reasons why, rather than accept a because I said so answer.
As an aside, a similar question came up this past Shmini Atzeres. Between Mincha and Maariv, the Rav gave a shiur on why Simchas Torah is attached to Shmini Atzeres and not Shavuos. It came up that Simchas Torah, in this ts current firm, only dates back to the Middle Ages. There is no mention of it prior to the Rishonim. I asked if that is so, why was it set up one way in EY ( on same day as SA ) and as a separate day in Chutz learetz? He didn’t remember seeing any sources. Does anyone have any sources for the difference?