Federal agents pounced on the fentanyl stash houses of gangsters behind deadly drug dealing at filthy MacArthur Park, with a slew of crushing raids May 6. The Post was there as nearly two dozen Drug Enforcement Agency officers swarmed the South LA stash house of fentanyl princess Mallaly Moreno-Lopez and her boyfriend and alleged partner in crime Tarfur Jackson-Lora in a daring dawn takedown.