I don't think he gave himself sepsis; that would be impossible, surely? One possibility is that, following loss of his toes and soles, he persuaded his surgeon that complete btk removal would give better liveability results (not implausible), but the insurers kicked off because it meant a bigger payout. Once he'd been accused of fraud, the police got a warrant, and found he'd been buying Gustavson's videos online, hence the 'encouragement' charge (mutilation illegal whether consensual or not). The trial should be interesting, if he doesn't cave and plead guilty.