First, I think that what nojustice said could very well be true about her being arrested because they thought she might flee. I'm sure they already had the phone that was found in her house. It could have been a quick charge to get her to stay while they gathered evidence.
Second, as I posted right after her body was found, the phone is not what directly led to her body. It may have helped and would have eventually led to her body. However, it was someone who worked with AL that had been talked to that day about the dump truck being stolen from the Argon shop in saline county, that called police and told them to check Cabot later that night. It was a combination of his possible access because of keys, his knowledge of the plant from his short employment with argon, and the ex coworkers gut instinct that led to the discovery of her body late Sunday night. (Past Midnight before they found her ).
Also, that coworker said AL had been fired for selling drugs while working.
Moo because I have no links supporting this theory/. Just local/inside knowledge of the party that helped LE.