I am not 100% positive, but I THINK that the koalas live at the Palm Beach Zoo on a permanent basis. I will look further into it though.
I always find the minimalist indoor exhibits that international zoos build for their koalas strange but Palm Beach Zoo takes it to a whole new level of simplicity.
That is true for most indoor koala exhibits in the U.S. however the Cleveland Metorparks Zoo's indoor exhibit is fantastic, and the San Diego and Los Angeles indoor exhibits aren't too bad either. However zoos like this one with koalas, their indoor displays are not so great. I did check, the koalas do permanently live at the Palm Beach Zoo.