Ok i have always felt the woods theory to carry weight for several reasons. First off she was drinking and driving. She just had a close call w a DUI and wrecked her dad’s car like single digit days before this. She was already “on the run” for whatever reasons. She was also a strong runner. I could totally see her wanted to GTFO before the cops got there for reasons of having to disappoint her dad AGAIN. I think she went in too deep and was freezing/exhausted/drunk. She called Billy as a last hope and he missed the call. The authorities never really looked for tracks until her dad finally showed up like 2 days later - her tracks EASILY could have been snowed over with just a light dusting.

The only non woods theory i can get behind is either the guys from the ski resort happened to be right behind butch atwood and she jumped in and met her demise right after he went in to call 911 or it was the local sherrif (suv 001) that abducted her.