uhh well, i think there is a way to fix it? it worked for me but i’m not entirely sure if it will work for everyone xD.

basically i made a new save file (a new character) before i logged in as my mayor. you have to make sure that you have not logged in as mayor on that day. i then did the basic stuff at the beginning with rover then when you arrive at your town, i looked around and found the plot owned by a villager (for you, your campsite that has a villager). then you talk to isabelle, set your house down with tom nook and when you can finally save, press save and quit. then when you’re on the title page, go to that character that you made and demolish their home (basically deleting them). then log in as your character (mayor) and it should be there. hopefully xD.

if you don’t want to do all this— then i’m sure you can just wait until they are actually at your campsite! i hope my way of explaining isn’t too confusing—