I’ll try:
My theory is that blood that was on darker surfaces such as the side of the car and the garbage cans was not obvious to persons not looking for it and apparently not cleaned up by the murderer(s). Blood other places was cleaned up by the murderer(s). But they did not do a good job from a LE detective point of view.
When LA arrived, she assumed she had to get her charges to the city on a certain schedule. She also was with 4 children who had all kinds of side issues and conversations about ketchup, lacrosse, you-tube, whose turn it is to do what when, fairness, and whatever else kids talk about.
Trying to get kids with you, focused on keeping to a schedule, one thing you do not do is spend too much time letting the topic of convo derail progress. “Yes, that’s weird, Mom forgot her purse... who can be in charge of bringing it to my car?”
When LA arrived, it was apparent something was weird about the day and evening before, but she was likely focused on keeping herself and the children on schedule. Jennifer was not yet missing. The weirdness was going to be a story, but a story for a time when she was not trying to shuffle 4 kids.
When LE arrived, Jennifer was missing, and LA, among others, was now worried. They reported Fotis’ past abuse and that he had a gun. LE was looking for blood. They saw some with their eyes, and by rumors, the garage “lit up” under black light which glows when it hits bodily fluids (among other things).
LA when in the middle of picking up the kids, and LE, when investigating a missing Jennifer who was quite possibly hurt by an armed abusive ex, entered the garage with entirely different mind sets.
Does that make sense?
I have another point. It does seem like LA handled the situation by using her car. (I don’t know, but it seems possible since team Fotis was trying to intimidate her about that.) If so, team Fotis got lucky. Maybe the blood on the RR would have been seen earlier, and LE would have been in Farmington in time for the drive back and forth party. 80MS <=> 4JX.
(I wonder if the RR keys were available? If they were where they belong, but LA used her car because she didn’t use the RR without permission or plans, that is not weird. If she would have used it but couldn’t find the keys, that is very weird.)
Team Fotis should be sending LA thank you cards for not using the RR. Whatever was happening at the secondary crime scene could have been interrupted, and there may never have been a dumpster date night.