Report them to the authorities. Manipulating market prices for the purpose of affecting an oracle to extract value at an illegitimate price is a criminal offence, it falls under market manipulation and fraud. It doesn't matter if code is law, the crime was in pumping the price artificially. The CFTC and SEC filed charges against Eisenberg for pretty much the exact same thing.
RE: ⚠️A few Hive and GLS community members colluded to steal more than 250k USD // Biggest theft since Justin// The GLS exploit explored