you've obviously out some thought into this so I'm taking your post seriously but in all honesty I don't get how this could be a realistic possibility. Speaking as someone from Brisbane's west, it's not cold enough out here in April to die of hypothermia even if not moving around. It's colder out here in Winter but paradoxically it's warmer out here in summer and we still get the warm weather in April. If she was stuck out here and cold there'd be traffic coming past or homes she could go to for assistance rather than freezing. As a theory it also wouldn't explain why Allison would be out this way. She wouldn't just decide to walk there, and it'd take ages, and she'd be seen. It's not near to her house foot wise. What would be the purpose for being there?