It seems like Hani is someone that doesn't ascribe to one thing but takes a few things from the 4 Aqeedah schools (Ashari, Maturidi, Athari, Mu'tazili). He even says in the same post that he agrees with Ahl al Hadith on a lot of points. You cannot really pinpoint what he is and this is why I'm not going to label him as a Mu'tazili.
1. According to Farid and his scholars, your chief writer would not be classed as part of the Ahlus-Sunnah wal Jamaah
2. Taking knowledge from him would be discouraged
3. In certain instances, some scholars would even question if he was a Muslim depending on his particular beliefs.
1. We don't even know what he believes in, which group or belief of the Mu'tazila does he subscribe to? Because the Mu'tazila are not just one group with the same exact beliefs, and supposing they were we would need to know what Hani subscribes to because he clearly says that he agrees with the beliefs of Ahl al Hadith as well.
2. There are situations where it can be permissible to take knowledge from Ahl al Bidah. Islamqa.info, the most known Salafi/Najdi website out there, stated that taking knowledge that wouldn't teach you Bidah can be permissible based on a few circumstances. They mentioned the Arabic language, Quranic Tajweed and Fiqh as things that would be okay to learn under people of innovation. Nobody here is taking Aqeedah lessons from Hani and all he has ever done is show the correct history of the Sahaba and the wars that occurred, as well as a few things against the Shi'i sect.
Plus, Muslims in the west go to Universities and are taught by non Muslims, possibly atheists, all the time. We work with non Muslims and we are bossed by non Muslims, etc. How come this is okay but taking a few historical lessons from a
Muslim that is just a bit confused in Aqeedah is not okay? That being said, nobody is taking knowledge from Hani, we take knowledge from the scholars which is what Farid does. Since you know, this is how it has always been..
Link:
https://islamqa.info/ar/answers/223300/%D8%AD%D9%83%D9%85-%D8%A7%D8%AE%D8%B0-%D8%A7%D9%84%D8%B9%D9%84%D9%85-%D8%B9%D9%86-%D8%A7%D9%84%D9%85%D8%A8%D8%AA%D8%AF%D8%B93. Not worth addressing.