According to your favorite field,statistics, the more he was there, the MORE EVIDENCE there would be. If he was there more than once, statistically, there is no chance he would not have left evidence.
Only true if nothing done that would remove evidence like smudging, cleaning, vaccuming etc.
But this whole speculation thing is dumb and its not what reasonable doubt is all about. Speculating that Danielle entered RV without any evidence is is as dumb as speculating that Westerfield visited Danielle's bedroom regularly. Either are possible but their is no evidence to support either and such speculation isn't used as reasonable doubt.