Candlemass singer Johan Längqvist was forced to miss the band’s September 12 set at the London Metalfest in London, UK after being hospitalized for a “medical emergency.” During his absence, Felipe Plaza Kutzbach (Procession, Deströyer 666) filled in. Aaron Stainthorpe (ex-My Dying Bride) and Tony Dolan (Venom Inc.) also made guest appearances. Candlemass commented before…