Napalm is quite useful in Virtual On Index, particularly with veteran mode Apharmd S players who like to forward dash inside their napalm, which matches speed perfectly. As far as I can tell, napalm is impenetrable in Index. It even blocks other maximum priority things like Bal jump CW and jump RTCW lasers (the graphics for the lasers remain).
Regular bombs don't have the same infinite priority in Index. They can typically be penetrated by any turbo attacks. Temjin's LTLW and jump LTLW bombs have higher priority and in particular are able to destroy the drones from Grys-Vok's super.