Yes, it was a terribly unclear and poorly written article
The daily mail has a better summary of events.
The pizza box was trash from his office. Police secretly collected it to find DNA. They found a strand of the perp’s hair, which matched a hair found in a burlap sack in which he buried one of his victims.
The link you sent went to another link to dailymail.co.uk and perhaps there is more in this one - started with a witness coming forward in May 2022 describing a car that was his Chevrolet - and a lot of burner phone calls and he was seen buying burner phones in May 2023 - WHATEVER - a great piece of detective work regardless...A little more than we had to go on than before...