While I don't agree there's anything wrong with teleportation, I'll counter you on the point I'm qualified to: Translation.

A) The game is set in a world where the theme is very heavily influenced by middle ages/renaissance Europe. And the FF series in general has always had a strong inclination towards western culture and English, utilizing katakana-ized English words for many, many aspects of it. So naturally the English localization is designed to follow the "old world" theme. Thus, they use old-style English. The meaning is still the same, it's just stylized with old English.

B) A lot of the names in FF series actually come from Scandanavian and Middle Eastern cultures... which are quite famous for sometimes lacking vowels. Some of the names are actually taken straight from Scandanavian folklore.

C) As someone who also is fluent in both Japanese and English, I disagree with you. The localizations are almost always true to the Japanese. They aren't always exact translations, but anyone who has ever worked in localization can tell you that you actually want to avoid exact translations in many cases. Because the Nuance and implications are often quite different.

Let's use your example (I'm at work so I can't confirm your translation of the Japanese, but I'll take your word for it): "I don't wanna die! Somebody save me!" vs. "I'm eternal! I'm immortal!"

Perhaps you're not familiar with many of the cultural nuances of English and the tropes of English media because you live in Japan, but those are not nearly as different as you think. In fact, that particular English trope has been used countless times in English literature to imply the same meaning as the Japanese. Essentially he didn't think he could die and is emotionally disturbed by the fact he actually can. And in English literature tropes, that fear is often met with ultimately futile, defiant language.

There is nothing in the script that is contradictory. There are a few times where it might seem that way because it's not an exact translation, but the meaning is still carried over. Their localization team is actually quite GOOD because they make use of English tropes to mirror the Japanese ones that don't really make sense when translated exactly.