On another board, this is being reported as a workaround (credit: P. Agarwal)
Just found a workaround. When u come to the room, continue forward and get into the door on the top. as soon as you reach there, take 1 step forward. Robin and all will follow u there. DO NOT DO ANYTHING and come back. When you come back, the path will be open and you can clear the tiles.
If you FREE Pete, then Robin blocks the 3 tiles and you cannot do anything about it except submit a ticket.
Please let us know if this is successful or not.