Found by The Cutting Room Floor Wiki, the arcade version of The Fairyland Story has a hidden staff list.

While it was assumed it was unused for a long time, this Japanese site explains that holding Magic after a Game Over gets it to appear in-game.

Here is a rough list of who these people are, and what other Taito games they're credited with...

Rolw in FLS Credits - This is the role attributed to each person in the hidden Fairyland Story credits list (translated by @slawbrah & @_kimimi)
Name in FLS Credits - ... And this is the name they go under in that list.
Real Name - Well, this should be obvious.
Initials - Some people, such as Tadashio Kimijima, hid their initials in the high-score tables of other Taito games. That's what these are.
Works - The games these people have worked on (in order of release)...
Role - ... And their given position in the credits for those games. Some had more than one position per game!

Role in FLS Credits Name in FLS Credits Real Name Initials Works Role
Original scenario
K.ISHIDA
Kazutomo Ishida
ISD
 Kiki Kaikai
Extermination
The New Zealand Story
Don Doko Don
Space Gun
Liquid Kids
Arabian Magic

Hat Trick Hero '93
Hat Trick Hero '94
Space Invaders '95		 Programmer
Game Programmer
Main Staff
Software
Software
Programmer
Producer
Software
Software
Software
Software Engineer
Planning/design
ONIJUST.H
Hiroshi Tsujino
ONJ
 Arkanoid
Cadash



Dr. Toppel's Adventure
Plump Pop
The Ninja Warriors		 Graphic Designer
Director
Game Designer
Production Designer
Graphic Designer
Game Designer
Game Design
Writer
Background
T.NISHIMURA
Toshiyuki Nishimura
(-)
 Continental Circus
Raimais
Superman

The Ninja Warriors		 Character
Staff
Director
Art Designer
Character Designer
Background
T.KITAGAWA
Tetsuroh Kitagawa
(-)
 Top Speed
Darius		 Graphic Designer
Art Designer
Music
Y.TSUCHIDA
???
???
???
???
Music
T.KIMIJIMA
Tadashi Kimijima
KIM
 Bubble Bobble
Metal Soldier Isaac II		 Sound Creator
Sound
Director
M. OGATA
Masaki Ogata
(-)
 Extermination
Plump Pop
Operation Thunderbolt
The Ninja Warriors

Dead Connection
Dino Rex
Cleopatra Fortune		 Software Support
Programmer
Project Reader (Leader)
Director
Programmer
Director
Producer
Producer
Director
M.HATANO
Mikio Hatano
(-)
 Kiki Kaikai Director
Cooperation
PACIFIC
???
???
???
???
Cooperation
KUMAGAYA
Taito Kumagaya Laboratory
(Ofshoot of Taito)
(-)
 Kiki Kaikai
The New Zealand Story
Liquid Kids
(-)
Cooperation
YOUGA
???
???
???
???

KUMAGAYA was filled in thanks to The Cutting Room Floor's page on Halley's Comet which also has that text.

Can you fill in any of the gaps on this chart, dear reader?

If you can, we implore you to get us on the horn, either via email (TheMetalSlug at gmail dot com) or on the Twitters.

We once did this for all the Irem/Nazca games. Wasn't a good idea.