Against popular belief, I'll field this with what I think MIGHT be a possibility.
I think Jodi did have help. I think her intruder story WAS true and she was the 'female'. (I mean, what was her advantage of making one of the intruders into a woman? It makes no sense)
I think Jodi lured him into the shower and this 'intruder' (perhaps Matt McCartney) came in through the back window (that a screen was found laying in the backyard and taken into evidence......) and a burglary scene was set in case a roommate came home?
Now the BIGGEST question I come up with empty with is: Why would someone help Jodi kill someone else?
I think the fact that this chick has a fan club after brutally ending the life of another... might be indicative of how people in her life (mostly men and now.....lesbians?) are drawn to her and obviously very dedicated to her too.
So if my theory is right, who knows why someone would help her. I think Matt was involved in the grandfather's break-in and most likely gave Jodi the gun and DVD player once she got down near Darryl's.
She most definitely bartered the gas cans for the stolen DVD player and THAT'S why the gas cans were never returned to Darryl (because Jodi own them now)
I also think she had a disposable cell phone besides just Gus Searcy's phone she had borrowed. I don't believe she drove phone-less for hours while trekking to Travis' house to kill him. I think she had one of those prepaid phones and was in contact with Matt, Gus and Darryl the entire time and in fact, I believe all 3 men are deeply involved in this event. Deeply!!