Worst case scenario:

Peronists (mostly unions) will riot/strike everyday. Milei won't have the power to counter. People will start to manifest against him. He won't call for early elections. He will escape. The country won't have gov. The central bank will shut down the financial system. People won't have their money. People will have to trade things for things (like toilet paper for food). Nobody will want to be the president in that moment (we had 5 presidents in 7 days in 2001). Will take long time until someone takes the presidential chair. The gov will be broke af. The gov will release a fake fiat money (a fake of fake money, patacones in 2001). After looking time that president will call for elections