In 2010, Nasa researchers found graphite – a mineral made up of stacked layers of graphene – in lunar samples collected nearly 40 years earlier by the Apollo 17 mission. After ruling out the effects of solar winds, they attributed the finding to the impact of meteor strikes on the moon.
The Chinese scientists acknowledged that the impact of meteorites could also lead to the formation of graphitic carbon, as proposed by the Nasa researchers.
If I'm understanding it correctly, it's a case of:
NASA finds graphene on the moon
The moon is generally thought to have very little carbon, so the theory is that the graphene was introduced by meteorite impact
CNSA goes to check out a patch of the moon that is, relatively speaking, quite new. As such it should have received fewer meteorite impacts
CNSA still finds graphene, so that's a mark gainst the meteorite theory
Due to the structure of the stuff that contains the graphene, it may be the result of volcanic processes. If this is the case, it's possible that the moon is not as carbon-depleted as we thought.
If that's true, it suggests that our theory on the formation of the moon could be wrong too, since we may have made incorrect assumptions about the composition of it
So NASA found something interesting a while back and made a best guess based on the data available, and now CNSA found some more data that might change the prior conclusions. On the other hand it is still possible that NASA's theory is correct, it's not like anyone found a billions-of-years-old recipe for the moon. This new stuff just tips the scales against it a little.