I was really, really sad after i saw about this question.
First of all, i'm friend of both Gino and Khan, but if Khan really WANTED Gino to get the game loss, i think it has been a very vad example of Spirit of the Game. My idea has always been: if it happens to a player to DO THE WRONG MOVE in a long game, i'm not for letting him back. Pokemon requires concentration and most of the games can change rhe result if it happens for one of the two players to do a misplay. So, as i consider misplay part of the game, and if a player misplay, it's right that he has to pay for it.
I consider that all the things that are extra-game and that are done for incident should not ruin the competition.
For this reason, i think that all of you can see that Gino's action was not cheating, but was clearly unintentional. 10 cards (the EXACT NUMBER to consider it a Ultra Pro production problem) and if they were not 4 ROSANNA, 4 BEBE AND 2 LUXURY or 10 BASIC ENERGIES there's not way this can lead to a chearing effort.
As unintentional could be to hurt with your arm the deck and reveal the first card of the deck.
As unintentional could be to throw a dice and hit the opponent deck revealing the first card.
So, my question is: would you come the judge if it happens to your opponent to hurt the table and reveal the first card of the deck? Or if it happens for your opponent to shuffle your deck and make a ROSANNA's SEARCH fall from the deck due to a shuffling problem? Or if it happens to your opponent to say "****" and this hurts your sensibility and you do want him to be given a Game Loss for Unusportive conduct?
The only reason why a person would do that, is because he want to win in all the ways no matter how.
So, if Khan did it just to win a game no matter how (and he didn't ASK the judges to LET Gino re-sleeve his cards), that man has no my support, even if he's a good friend. This was a bad proof of sportmanship.
But well, apart from this, we are here to talk about the judge side.
From my experience, i would have give a MARKED CARDS: MINOR PENALTY for this reason.
MINOR PENALTY covers the possibility of manufactoring errors and random bented cards. These 2 parts are important. I know that the problem was that not few cards, but 10 were ruined, but i would ask you: does it really matter? I think that in the Pokemon game, it doesn't matter if 2-10-30 cards are ruined in THE SAME WAY.
I mean. If it happens to have some cards ruined, some cards with a different color, so cards longer than others...ok. But if it happens to have 10 random cards ruined in the same way, does it really give you more advantage than having just 1-2 key cards ruined in the same way? Wouldn't be worse a LVX or a 4x than 10 cards random?
Then, i'm gonna explain why i WOULD NOT have give a MARKED CARDS: MAJOR PENALTY.
The MAJOR PENALTY comes in action where there is a "noticeable pattern" and "Because the possibility for a player to gain an advantage is high, the penalties associated with his category are more severe".
To be specific, the guidelines make us some example "4 Candy bented, all the basic energies ruined, some key cards with thumb marks".
In this case, we are very FAR from that. We don't have any suspect (noticeable pattern) because the 10 cards cannot give any real advantage (what's good in havind 2 Drawer, 2 Candy, 2 Fighting, 1 Trapinch and 1 BTS bented?) and our example isn't even near one of the 3 examples reported in the Penalty Guidelines.
So, my point is: as we are in a case of MANUFACTORING ERROR and there's not even the suspect that the cards are ruined for a purpose (and MAJOR PENALTY seems to be created to punish the players over we have some suspects), the penalty should fall under MINOR PENALTY.
If you consider that MINOR PENALTY is too low because of the number being 10 and not just 1/2, you should apply something bigger than WARNING.
But again, as a PokemonProfessor and with the GuideLines in hand, i don't see any reason why a Judge should follow the MAJOR PENALTY issue (except from, and if it was happened i wanna know it, the 10 cards checked by the judge which issue the penalty was considered by the Head Judge of the event to have "possibly given an advantage" to the player).
If the Head Judge was not told about it and, something even worse, the 10 MARKED CARDS WERE NOT CHECKED BY THE JUDGE, i believe that the judge who gave this penalty did a very wrong choice.