Renou

Okay but I only have 4 badges in johto so I can't get back in kanto right ?

Hello , I have the 60k and the (OT) ditto but I just don't know where is the npc who exchange me the bike voucher (Not in route 30). I already tried to speak to bike salesman in goldenrod city but he keeps telling me that his bike cost 9,999,999,999. Thanks.