I was just thinking a little more about this.
There probably aren't very many AirBnBs that are reserved/rented out each day in London, Ontario- especially in mid-August.
If someone wanted to determine whether or not Luke actually WAS staying in AirBnBs, they could start by doing two things:
1) see if any of Luke's relatives are in the AirBnBn business, that's the obvious one
or
2) check any archived examples of the AirBnB webpages for the last couples weeks, count out how many were rented out per week,
2-A) Do the same thing for this past week, then monitor throughout next week, and see if that amount seems to signifcantly deviate from the mean of the previous weeks (could probably calculate daily means for every day since august 1st, and go from there). If the daily means starting at, like, the 16th or so are higher than they should be, it could mean that Luke is actually telling the truth and running around to different AirBnbs.
From there, wouldn't it just be process of elimination, of seeing which listings get taken down, day by day, and digging in further on those individual places?