The real hidden vote is all the military men and women who came home from Afghanistan and Iraq. In 2008 and 2012 they were disenfranchised. That’s a could of hundred thousand.
That can swing an election.
Your assumption of the military vote is may be correct but its impact is dependent upon how that vote is geographically distributed. Many members of the military reside in red states so their votes will not affect the Electoral College count.