I believe a case can be made it's a 2-throw penalty for not having your disc marked with the original manufacturer's model indication. That includes discs that are tie-dyed. It can easily be fixed just by replacing the original marks, sometimes in the field. But are players leaving the Innova 2-letter ink mark ID on the bottom?
Per 801.02A Discs used in play must meet all of the conditions set forth in the PDGA Technical Standards.
Per Tech Standards section I.(B) As of July 1, 2010, all newly-approved discs must carry the approved model name either engraved in the mold or as part of the disc art, permanent sticker label or by indelible ink marking. The full model name is recommended, but the use of unique abbreviations or codes is acceptable. Such codes must either be identified with the submission for approval, or supplied to the Technical Standards Committee for variants produced after the original approval.
Per 801.02 D A disc that is questioned by another player or an official is illegal unless it is subsequently approved by the Director. AND E. A player who throws an illegal disc during play shall receive two penalty throws, without a warning. A player who repeatedly throws an illegal disc during the round may be subject to disqualification in accordance with Section 3.3 of the PDGA Competition Manual.