Bug? The curious case of cankered chief -Help

I’m standing right next to the body I need to dematerialize, press and hold the trigger and it mists over body, but never decomposes it. I’ve tried standing on top, behind, to side. I’ve held for a long time, short time, etc. Nothing seems to work.

I’m wondering if I have to upgrade the dematerializer to finish this quest? It only states that I need it, but perhaps I missed an upgrade prohibiting me from dematerializing?

Any help would be appreciate!