Like I said, the simplest solution is usally the best. So I'm going with being "from Iowa" means Kirk was born there. And the Kelvin was headed back to Earth so Jimmy could be born in George's home planet/country/state/town.But that doesn't mean you were born in all those places. Home is where the heart is, The family farm in Iowa may be "home" but he may have been born anywhere else. Maybe he was born on Tarsus IV and moved to Iowa after the massacre. Home would be the place where he feels comfortable and safe.
The point is we don't KNOW that Kirk was born in Iowa and we don't know the Kevlin was en route to Earth.
Me, I'm from Georgia but raised in Japan, Texas and California.