That's why I asked about the order they joined. Looks like he's shuffled the order of events compared to the originally published silver/bronze age comics. And the Titans roster is a bigger deal than the fact Donna gets her modern costume too early (the Doom Patrol were already dead - in 1968 - by the time she started wearing the red pants - in 1969 - but that can pass considering Dick and Garth's costumes have also been updated). If Lilith joined years before Bumblebee - and both were present until the cancellation before being replaced when New Teen Titans launched - then it means Lilith should be on the team.