It's not clear who did what on this feature. Jerry Bails lists both Paul and Nils as pencil and inks.
All Gustavson credits, as they now appear above, verified and courtesy of Terry Gustafson, son of Paul Gustavson.
Signed on splash, also as S.G. in the corner of the final panel.
Writing credit suggested by the Who's Who.
This is the only one of the four Fire-Man stories not signed by Martin Filchock, who wrote and drew the other three. Jerry Bails' Who's Who also lists Charles Verral as a writer for this feature (but does not list any other artists). Based on Who's Who and Filchock's other work for Centaur, he almost certainly wrote the three he signed, so this is the only plausible Verral-authored story.
Jim Vadeboncoeur, Jr. agrees that this story was penciled by Filchock, but it's possible that this is a different inker.
Alter Ego #117 (June 2013) states that Filchock did inks as well as pencils, so ? removed.