Technically, the moderator may be even Chinese. But the Chinese never catch the whole meaning written in the Russian section. For this he needs to become a Russian - So he must be Russian
I don't agree at all with your assertion. A ТРКИ-2 level foreign user can understand the main ideas of complex text on both concrete and abstract topics, including technical discussions in his/her field of specialization, can interact with a degree of fluency and spontaneity that makes regular interaction with native speakers quite possible without strain for either party, can produce clear, detailed text on a wide range of subjects and explain a viewpoint on a topical issue giving the advantages and disadvantages of various options.
However, if you want "humor" to be recognized a proficient user like the ones at the ТРКИ-3 and ТРКИ-4 maybe up to the task.
I could have agreed with you IF you were saying majority of Chinese users are not at levels high enough to be a ТРКИ-2, -3 or -4.