Partly, this is because her pronunciation of the R (especially combined with the o), is really bad. She's using the french R (or something that resembles it a bit), instead of the rolling R that most Dutch speakers use. Please ask someone that you know to pronounce it for you!
I'd say that the pronunciation of the "r" varies greatly from region to region. I've heard native speakers who roll their R, and others who use a French/German R when the R is initial in a syllable, and an "English R" when the R is at the end of the word or before a consonant.
Well yes, I agree, there is a huge variety in pronunciation of words and also the R if you would pass all the regions between Groningen and Brussels, but I feel that Duolingo should be teaching General Dutch (Algemeen Nederlands) and I didn't agree on how the previous voice pronounced the word.