PSA used to have a “custom encapsulation” option with a green label, mainly for novelty things like your kid’s little league soccer card. But there was a brief moment sometime before 2015 where they allowed some FPO and matchprints through, because they didn’t qualify for the official red label.
Mostly it was one guy who graded them: Can PSA grade/authenticate this card? - #9 by xgav1337x. Obviously they are still floating around today