Why are the remaining season 3 episodes not available?
The season is on break until July. Once Doom Patrol has finished its run, the last half will run in unison with Swamp thing I believe.
It should be back in June, @One-Eyed-Wilson, but I agree about Doom Patrol 
@unix.gnuru.78870, if interested, here’s the official statement for such: YOUNG JUSTICE Enhanced Episodes and OUTSIDERS Prequel and Documentary Coming!