[loriverkutya]

I'm not sharing the view on the difficult the work with part.

For me, this just means, that he is not accepting a solution to the problem, explaining why he thinks it is not a good solution and offering another one, which would work for him. Also, he is not dismissing the hackerrank test, but asking to evaluate his skills on a different way too.

As far as I see, this is probably the best way to argue with somebody, that their chosen solution to the problem is not the ideal based on your knowledge and experience.