I'm sorry but unless you work for SEGA and make those decisions yourself, you can't confirm anything. I know you tried, and we really appreciate that, but it's their game.
I'm not expecting it to ever happen, but with the positive reception for 0 I hope the series begins to catch on here in the US and maybe they'll reconsider down the road, even it takes some work on their end. Doing reprints of 1-4 is a good sign that there's demand for all the games in the series.
That said, I imported the Japanese Y5 release last year and played through it, so either way I'm happy that I do at least have the game on my shelf.
So where could I go if I wanted to see all the latest physical releases in my local mom n pop shop?