You said that you use an "instance variable in its (player's) name"
Why not change this (not use at all) and use only one GLOBAL variable to do this job?
It can be called PLAYER_POSITION and every time he moves somewhere like GROUND23 you can SET this PLAYER_POSITION to 23.
Using this 1 GLOBAL variable you always know where your player is and therefore can direct him anywhere you wish such as if PLAYER_POSITION = 23 then put player into position 13.