You're welcome :)
Have you read the lesson notes? I don't know by heart whether it was mentioned but chances are on yes, imo.
For conjugation: better get used to it, I don't think it was very special. Would you think "they" can refer to one person? (And this is not a new thing, nevermind the "rumors".) In German, formal "you", regardless number, is "Sie" ~ "they", with 3rd person plural conjugation. In Polish, it's like Hungarian as far as I know, separate singular and plural, both 3rd person.
I'm not sure about the app; on the website, you can click lessons and you have three options - starting the lesson, taking the level-up test (the keyhole icon) and reading the notes (the bulb icon).
I'm just guessing, this may be Basic 2 (https://www.duolingo.com/skill/hu/Basic-2-alternative/tips-and-notes) and unfortunately, it only slightly mentions ön and önök without any remarks on their usage. I think it would be the bare minimum to mention they go with third person conjugation - this was no problem for the Polish course; no formal speech excercises (at the beginning) yet they did mention it was going to be third person conjugation.