Can they deduct all of the money they spent to hide his birth certificate, college transcripts and loan documentation, etc.?
Unfortunately they are not using their own funds for that. You and I are paying for some of it.
If he is using his own money for the lawyers - Yes he can.
(paraphrasing) 'All legal fees relating to your employment, as being necessary in keeping you job, can be deducted and itemized on Schedule A.'iirc, That law's 'intent' was for suing for things like unlawful dismissal like in discrimination - age, sex, handicap, etc. But it's not written that way so it's open ended and ripe for loose interpretation (and misuse).
I guess the pols would call that a 'Loophole'.