The problem is that, in Japan, Korea and China, “the written rule” is secondary. In practice, the referee’s decisions, based on historical precedents, tradition and the general consensus opinion of the professional players, is what matters, even if it contradicts the written rule, which works as the general “guide” but can be overridden if a rare, strange position appears.
This is something critical, that most western discussions completely miss, probably due to a “western thinking vs eastern thinking” difference. A phrase like “You could check it yourself” is actually sort of a trap: unless you research what the actual historical precedents and consensus of the Chinese Pro Association is for a certain rare repetition position, the written rule is not enough to clearly know how the Chinese rules would handle it (unless it happens to be one of the specific examples mentioned, like moonshine life).
As hexahedron pointed out, the written 2002 chinese rules say something like “in principle repetition of the whole board is forbidden, but for some positions like triple ko, eternal life, round robin ko etc the referees can void the game or apply other rulings depending on the specific cycle”. Triple ko (or any other infinite repetition during the “main game”, not just at the game end when everything is completely settled) = void game / draw is as far as I know the universally accepted result in China, Korea and Japan.
For endgame-appearing repetitions, “moonshine life dies” and “unbalanced repetitions cannot be played” (sending two returning one, sending three returning two etc where one side captures more stones in each repetition) seem to be used in the actual Chinese rules, and should be the most important and common precedents.
I have not idea how the Chinese would rule a “bent4 + double-ko-seki” for example. A triple ko would appear when one goes for the kill of the bent4 at the end of the game, unless superko is actually used in that case as it is for moonshine life. Does anyone know what the actual Chinese would do in that case? Apply superko, or void the game if killing the bent4 instead of seki matters? I doubt that there is any professional precedent, as double ko seki + bent4 in the same game sounds so incredibly rare…
An even more fun rule monster question is to take a bent4 + unremovable-ko-threat (seki) , so that the bent4 lives under chinese rules (as is shown in Life and Death under Chinese Rules). Now add in addition to that a double-ko-seki on the board. Does the bent4 still live? Or is it now a void game due to triple ko? Or maybe the bent4 now dies instead of living, in a similar way to how the “one sided infinite repetition” of moonshine-life means that the attacker wins? Unless there is a professional Chinese game precedent or a specific statement by the Chinese Association about this positions, it seems impossible to know what a referee would decide.
