zenith ver. 1.2.3-1.20.1

Not long ago, when I decided to create my own modpack with the Zenith mod, I decided to translate it into my language. It turned out that during the translation, there were some small problems, and this... the absence of certain lines in both translation files. Elements in ru_ru.json that are not in en_us.json:
Additional achievements and descriptions:
"advancements.zenith.hellench": "Пропитанный адом чародей",
"advancements.zenith.hellench.desc": "Зачаруйте адскую книжную полку на уровне 70",
"advancements.zenith.upgrade_hellshelf": "Наполненная адом",
"advancements.zenith.upgrade_hellshelf.desc": "Улучшите адскую книжную полку.",
"advancements.zenith.seashelf": "Ярость морей",
"advancements.zenith.seashelf.desc": "Заполучите морскую книжную полку",
These achievements and their descriptions are missing in the English version.

Elements in en_us that are not in ru_ru:
Additional achievements and descriptions:
"advancements.zenith.deepshelf": "Delving Into Darkness",
"advancements.zenith.deepshelf.desc": "Activate a Dormant Deepshelf.",
"advancements.zenith.sculkshelf": "Embracing the Sculk",
"advancements.zenith.sculkshelf.desc": "Create a Sculkshelf using a Warden Tendril.",
"advancements.zenith.infuse_seashelf": "Sea Infusion",
"advancements.zenith.infuse_seashelf.desc": "Obtain an Infused Seashelf through Infusion Enchanting.",

And this is not the only issue. I would like to know why this is the case? And why does en_us.json have "/Adventure Module" while ru_ru.json does not... but at the same time, ru_ru.json has "/Deadly Module" which is not in en_us.json?
Thank you in advance for your response!