I very strongly do suspect that the author(s?) isn't a native English speaker; based on the particular grammatical errors, like slip-ups around the definite article, "Russian hacker" was an educated guess and not pulled out of an RNG. The issues with the writing go beyond spelling and grammar, though - things like maintaining a consistent voice (i.e. not switching between "I" and "we") are fumbled.

I think that's somewhat beside the point, or perhaps reinforces my point: as someone who's known many journalists in my time, professional journalists understand the importance of good writing, and thus inevitably come to understand the importance of good editing. I can go onto foreign news sites based in just about any country in the world - Al Jazeera, YNet, RFI, NHK, RT, Reuters, The Pyongyang Times - and find English articles written by non-native English speakers that aren't sloppy in the way this is, because they're professional outfits that ensure through rigorous editing that the quality of their writing matches the seriousness with which they pursue journalism. Any journalist worth their salt with a big scoop would want to ensure the way it was communicated in words came across as legitimate.

Hell, this isn't even just a journalism thing. I can log onto JSTOR and read papers in English written by scholars all over the world who aren't native English speakers and who aren't even supposed to be professional writers, and the quality of the writing will still be better 95 times out of 100. It's about professionalism, and like I said in my other comment, they're just obviously not professionals in any sense of the word. It's amateur.