1: Mod will be abused. It's a public mod. You cannot stop people from abusing it.
2: If the modder wanted there be no abusing, he would have either put it in VIP or set DMG / Def to 5x or both.
When modders release free mods for such highly protected games with high multipliers, they either:
1: Want the forum traffic and clicks. They don't care about the future of the mod.
2: They know of other different ways to mod the game so they use one for free.
The devs make 10s of millions of dollars in profit from this game every month. They will patch this very soon.