Confirmed by BloodyDisgusting, Swamp Thing has been canceled after the airing of the May 31st episode. Why? Well, no official reason was given but it's been clear from the beginning that Warner Bros. has no faith in the series, which is why they slashed the budget and episode order just as we were learning of problems with the streaming service itself. If the platform is struggling you don't want to waste money on a show that may be a loser.
So far nothing has happened to Doom Patrol or Titans...yet. I say "yet" because Swamp Thing's first episode was generally well-received, and had the superstar backing of Aquaman director James Wan, and yet it still got canned. There's a precedent being set here, and fans of DC Universe should be worried.