Oh my god, what an absolute load of bollocks, they've lost the plot!
There would be traces of her in a house she lived in for 20 years up to the day the lunatic bobby showed up. Clothes in a laundry basket, hair in the shower plug, a toothbrush, fingerprints, spare shoes, a mug/spoon/glass. It is not viable that in the few seconds in which she fled she managed to take every single belonging.
I'm sure the police must just be watching and waiting for them to slip. She's dead, they're concealing it, they mustn't get away with this!