In Shadowland pre-patch, botanica/Mechanar/Arcatraz are available for lvl20-25. But these dungeons require a flying mount to reach and players at lvl20-25 don’t have flying mounts. Unless we can queue using Chromie Time, there is no way to reach these dungeons even if they are made available.
normal work around for this type of thing is to hookup with a warlock and get summoned into the instance. We had to do this years ago and should still work.
you go to area 52 and use a borrowed mount…its there somewhere…slow but it gets you there