This operation seems exceedingly large for just 1 body, especially when the body has been recovered. With multiple sites being covered it's unlikely he could of created such a large crime scene in the time it took for his arrest from moment poor SE was taken.
The mention of the Micro SD card at his house and this being raised makes me think this was a significant find and lead this operation into a whole other direction.
With resources at the woods, the golf course, his garage and house I wonder if they discovered the SD card contained photos of other bodies and the subject WC in the photos directly linking him rather than just been a private horrible photo collection. Imagine the TV show Dexter when he had the blood slides and he hid them inside his house - most serial killers will take trophies.
Police installing porta loos at the house, and the golf course along with cabins and the mobile command units - this is a very large case and in the event of 1 body they wouldnt need this many resources. Theres been murder scenes where the body has been discovered then its left to a small team to clean up / collect evidence.
Three scenarios I think
1. All of the above writing but they dont have enough evidence to connect him to ALL cases - they dont want him to get just 1 life sentence they want him to never get out.
2. MET are taking this EXTREMELY seriously due to the damage it is causing PR wise and they have been told to use every resource.
3. Both of the above.
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Aside from all this discussion I want to say my heart breaks for SE family - I hope they get justice and if hes found guilty he needs to rot in a cell for what he has done.