It's a known, rare bug.
It also happen with forcefield to mindslayer, and with momentum to marauder.
Sometimes a sustain is stopped in a particular set of circumstances and every drain and sustain cost stays, and is even multiplied. It's a bitch and it's not even guaranteed a mod can fix it.
I write guides and make addons too now, apparently
You can go here for a compilation of everything I wrote, plus some other important stuff!
Includes general guides (inscriptions, zone, prodigies), and class guides (Demo, Anorithil, Bulwark, Zerker, Sblade)
There was a similar bug with steam after EOR came out. Rarely, after a character death steam generation would be vastly reduced or go negative for no apparent reason, regardless of sustains or steam generators. All 4 of my first EoR characters got it by the time they reached the end game.
Thankfully the bug seems to have been squashed in the last few versions.
"You could skip it, i think it drops 0 xp and 1 copper [at most], you are better off selling oxygen to beggars to become rich."