That's not an uncommon thing to happen, even though it should not.
From
this thread about the same subject, and the information in this one, I would guess that reloading to a point before you exited, and trying again, might work. Otherwise you can try it with resting before you leave, that might work too. Having the items identified or not doesn't seem to have an influence on your teleporting abilities, assuming there is only one cause for your inability to leave the island.