But there's so many reasons the garage could have been open. When I lived in NC, I lived in a subdivision just like Lochmere. Nice homes, neighbor parties, garage doors closed (you'd actually get a ticket from the HOA if you left it open). But there are so many legitimate reasons to have a garage door open (it could have been open only a couple of minutes - coincidentally when she walked by). Exiting the house thru the garage, trying to find something in the garage and wanting some fresh air or addtl daylight to find it, cleaning it, etc. If the garage was open for hours, I'd find it unusual. But we're only hearing about a minute while she walked by.
I get the "linking of coincidences" in a circumstantial case, but I think this is a stretch. If she saw BC stuffing something in the trunk, that would be another story.