pickup day, dove got up at day break and made the hour-long adjourn tee to brett's neighborhood, where a trash truck used just for schrauben's garbage brought it to a nearby parking lot. >> we'd have the truck dump the trash somewhat in a pile here, regardless of the size. >> right on the tarmac? >> right on the tarmac. scatter everything out, open every bag, get down on our hands and knees and slowly sift through every piece of paper that looked like it might be a document of some kind. >> reporter: and that's how dove's team found this coffee-stained phone bill showing call after call from schrauben to sandra's son, tom in arizona. >> and that number, tom's number, how often would that pop up? >> i think the average we figured out was about 24 times in a billing cycle about a month. >> almost every day? >> every day, correct. it was almost like going through a crime scene and finding pieces of evidence. it's an excitement that you realize, this is going to work. we are going to find what we're looking for. >> reporter: but there was yet again a problem.