Hey, I get corrected all the time when I refer to it as Anglo-Saxon and imply through word or deed that it isn’t a variety of English, but rather a predecessor language. It is Old English, and therefore English, and therefore the same language.
Danish and Swedish and Norwegian are all different languages, though. No doubts about that whatsoever.
Yes, the things which got written back then tended to be formal and therefore tended towards the poetic and flowery. I have no illusions that the normal everyday speech of that time sounded anywhere near as mannered, but nobody wrote down the normal everyday speech of that time, so we don’t really know what it sounded like.
It does not help that she has pretty poor syllable definition, though at times she sounds like she hits it - and then the words are distinguishable, even if their meaning is not.
When someone is not separating the syllables all that well, they run into each other and its hard to identify each word and the correct parsing.
Also, bear in mind that the person speaking does not seem to have any native accent, which cannot be right - travel around the UK and you will get different accents and dialects in regions literally only 10 miles apart.
I think her own base accent just does not work at all, she sounds far too RP for me, it just does not match the tone of the passage at all.
So in answer to the OP, I don’t think she even slightly sounds like Old English, not in the least, as to what Old English does sound like, I confess I don’t know, but it surely does not sound like academic studentspeak