of course which is why they killed him to keep the information he had.
If he had a “dead man’s switch”, they probably found it before killing him. Now everything is tied up neat and tidy. The man was depressed, his life was ruined, so he simply killed himself. But how? Impossible to hang oneself in a cell with a nine-foot ceiling, bed sheets made of paper, no belt, etc etc. There was another thread that discussed these details.