> the more liquidity that gets dumped on a particular outcome, the more motivation there is to tamper with the real-world outcome

This only works if there are enough people betting on the other side. It's not some kind of magical money multiplication machine. As more stuff like the one-day Iran bet or the 64:56 minute press conference happen, people will avoid taking bets on highly specific outcomes.

On more reasonable bets like "war with Iran in the next 6 months", if there is some kind of shadowy cabal putting billions of dollars on the yes side, they just aren't going to have much upside if there isn't the same amount on the no side.