I just did a defense test with Daedaleus and grevious burn is one possible burn that can be inflicted per action so that might help somewhat. Otherwise I think I might run my 4* dupe Navigator with explosive on Powerslave to try and make a dent in that challenge.
I don't know of any other characters that can do it either.
I'll have to do perfection corruption and seal the hard way with FotD Eddie, Sentinel Lilith and magus chopper again and Assassin CR for the seal, with a little help from troopers who have primordials...