Do you think he adjusted his story because of the media backlash?
He clearly spoke to a lawyer between the first night's interview and the days later videos and followups - notice how he emphasises that he wasn't following Martin. His lawyer would rightly have told him that chasing or following Martin would, if proven, send him to the slammer under the circumstances.
So his story becomes all about the address, which is an odd thing to check for behind the row of houses. Also that story about Martin circling his truck is just bizarre; why wouldn't he have pointed that out on the phone?
There's a point where his denials of chasing Martin become so ridiculous that the investigator laughs at him. It's pretty bad.
I think that to win, he'll have to prove that he had no intention of getting closer to Martin as Martin ran away. I don't think he'll be able to do it.
His lawyers are likely getting the videos out in an attempt to avoid putting him on the stand. The videos are a way to testify without getting up and being smashed on cross examination.