confused about Togepi and Togetic's Japanese names according to Bulbapedia

Togepi's English name is a transliteration from its Japanese name, トゲピー togepii, but for some reason Bulbapedia writes the romanized as "Togepy" everywhere. this makes me very confused, as that is 1, not what the katakana (letters) say, and 2, not possible to write in Japanese because what we call Y is exclusively a consonant, and you cant end a word on it. even the Name Origin of the article part says that both the English and Japanese names are from the same words, quote, "刺 toge (spike) and ピヨピヨ piyopiyo (onomatopoeia for a bird chirping)". that literally says ピ pi. there is no "py". so my question is, am i just missing something?? is Togepi written as Togepy using the latin alphabet in some Japanese media somewhere? or is this simply an error that should be fixed..?

then, Togetic's Japanese name, トゲチック togechikku, which is apparently a combination of, quote, "刺 toge (spike) and chick (a baby bird)." (chikku being a Japanese transliteration of the English word "chick"). this makes sense i guess, it's a lil birb :3 - however, my question here is, was the original translation from Japanese "wrong"..? did they not know it was from the word chick, and instead made the name "Togetic" because of how チ chi is often used to transliterate the sound "ti" from other languages? (because it does not normally occur in Japanese and is therefore apparently difficult and clunky to pronounce and/or write) cus i've heard some of the translations in the first few games were a little.. weird, sometimes... does anyone know?? i'm curious