If he were loitering, why would he been noticed and found?
I only ask because trained FBI profiler, Jim Clemente, said on his podcast that BG likely did wait for his victim(s)
"I don’t think he could have known, they couldn't have been targeted victims, I don’t think he could have known that they were going to be there. I think he setup his trap and they fell into it. But I think he had to get them to a particular place so he could have privacy to do what he wanted."
And
"In this case, I think Abby and Libby just happened to walk by and fall into this guys trap. When people are victim hunting, they are looking for vulnerability, availability, and desirability. And at times the desirability factor is just anybody who is available and vulnerable."
122 | Worst Case Scenario: The Delphi Murders from Best Case Worst Case