I’m thinking (well, hoping) that there’s still a chance that he’s still alive.
Bear with me here: Andre could have had people watching Will and other members of the Brady family to, I don't know, dig up dirt on them, use them as leverage. Will’s “watcher” saw him enter Ben’s apartment building, saw Ben enter the apartment building, then like a half hour later, he saw a hooded guy drag a huge duffel bag to Will’s car, shove the bag in the trunk, and take off.
He reports this to Andre, who assumes that Will was murdered. Will’s watcher follows the car to Will’s apartment. He saw the guy enter the apartment, then a few minutes later, he left. The watcher goes inside the apartment and confirms to Andre that it is indeed, Will. Dead. Andre, thinking fast, orders his man to inject Will with a revival drug, which the guy conveniently has in his car. He injects Will, and rushes off just as Gabi drives up. The revival drug brings Will back to life, but also puts him into a sleep so deep, not even Dr. Dan would be able to tell he’s alive.
The drug lasts long enough for Andre to snatch Will and transport him to a DiMera compound in Europe to reprogram his brain and turn him into a DiMera soldier.
edited to write out text speak - JS