There's likely no easy way to prove that you haven't been abusing the merit system. But, it doesn't matter too much if it's being abused on a small scale. It will likely only become a problem if a merit source was abusing the system and there's ways to tell whether they are abusing it.
In this case this is bad according to Welsh input on my merit system flaw.
If the moderator is a merit source an action is required for this sort of phenomenon.