were you obsessed? when i have somebody i m hunting down, i don t stop till i get em. isn t that being obsessed? i don t know. dedicated. get the answers you need. i m not going to stop until i do get the answer or the answer comes. reporter: but holbert, still, wasn t providing any answers about kelli. who had now been missing some-18 months. by this time, marshburn had spent thousands of hours and some $40,000 trying to crack holbert. he was losing hope and considered quitting. or even trying something drastic. at times, i wanted to just take nick and cut his fingers off. and say, you tell me, or i m going to chop another one off. i wanted to torture him because i knew he knew. you really would have done that? oh, yeah, i hated him that bad. i despised him. reporter: marshburn didn t resort to torture. but he did need a new tactic. something that would make holbert, finally, share his deadly secret.
did you take david marshburn seriously? absolutely. he came to us, and wanted to befriend nick holbert. what did you think of that? hey, go for it. we can t tell him what to do. reporter: marshburn, remember, is a private eye, not a police officer. and unlike detectives, he could try tactics that were, to say the least, unorthodox. a few months after the they met, marshburn told holbert that the da was ready to cut a deal, if he confessed. marshburn even presented holbert with this very attractive plea-bargain agreement. it would be something like manslaughter. and he would do three or four years. and he would go to a mental hospital. reporter: the so-called deal was completely bogus. i put a fake judge on there. it was justin f. case. honorable justin f. case. just in case. did he believe it? yeah.
she was a young female. that s not right. reporter: marshburn is both a bounty hunter and private investigator. his specialty? finding people, dead or alive. i knew she wasn t alive. i knew she needed to be found. she seemed like a really nice reporter: remember that tv interview nick holbert did? marshburn saw it, too. when i m watching him, it s like dude, i can tell you are lying. he did it. he knows where she is at. he killed her. reporter: and he was also convinced he could find kelli bordeaux. operating on his own time and own dime, marshburn started carefully researching the details of kelli s disappearance. i don t know what the hell got into me to do it. i mean, i just did it. to bring some answers to her family. yeah. i love doing it. i love helping a family out. reporter: marshburn was convinced holbert had buried
ground. the soil was loose, like a hole had been dug and filled in. it was at that moment, marshburn was overwhelmed with emotion. at that time, i said, baby girl, you going home. you going home, baby girl. so, i m sorry. i get emotional. had you even seen her, yet? uh-uh. you just knew? uh-huh. we just knew. reporter: but they had to be sure. so now, the grim task of digging began. we found little piece of the jacket. when we pulled that jacket back, that s when we stopped. we said, this is her. you know, i mean, this is it. reporter: throughout the day, marshburn had been texting fayetteville police about his progress. now, minutes after finding kelli s body, he sent them something definitive and dreadful. a photo. it appears to be a human bone. a place he s digging. and at that time, we contacted him and said, hey, cease and
marshburn, i m a private investigator. i m here to try and find kelli bordeaux. and i think you can help me. reporter: his strategy was simple. trick holbert into thinking that he was an ally. it was, basically, telling him i m i m your angel. i m your help. let me help you. help him how, though? for people to see the light, that he was not guilty. reporter: and he buys that? hook, line, and sinker. reporter: so now, the bounty hunter and the prime suspect talked. over the next few months, marshburn, gradually, started to win holbert s confidence, coaxing him to confidence about what really happened to kelli bordeaux. i had to get into his mind. and see what he was about. did you think that he was going to just confess to you? uh-uh. i knew that. i didn t know how i was going to get it out of him. reporter: at this point, police were aware of david marshburn and his diy investigation.