Here's some more detail on the question of not placing prize cards:
Game Play Error
7.1.2. Major
When game state has become irreversibly confused due to game-play errors, it is appropriate for the judge to issue a higher-level penalty. Major game-play error penalties are also appropriate for minor game-play errors that have left the game too confused to reset. In addition to the assigned penalty to the offending player, a Caution should be issued to the player’s opponent for not properly keeping track of game state and rules.
Examples of Game-Play Error: Major include:
• Shuffling your deck mid-game without the use of a card effect.
• Insufficiently randomizing your deck.
• Failing to place Prize cards at the beginning of the game*
• Drawing a Prize card without Knocking Out a Pokémon.
• Drawing too many Prize cards after Knocking Out a Pokémon.
• Forgetting to place damage counters on a Pokémon from a mandatory effect, such as Poisoned.
• Using a Poké-Power when a card prevents its use.
Recommended Starting Penalty:
Tier 1: Warning
Tier 2: Prize Card
*If the Head Judge determines that the offending player gained significant advantage due to this error, the starting penalty should be escalated one step. If the Head Judge determines that game state is irreparably broken, this penalty should be escalated to Game Play Error: Severe.
7.1.3. Severe
In some cases, a game-play error occurs which irreparably breaks the game state. In these cases,there is no way that either player or a judge can reset the game to the point where it can be continued. In addition to the assigned penalty to the offending player, a Warning should be issued to the player’s opponent for not properly keeping track of game state and rules. Examples of Game-Play Error: Severe include:
• Shuffling your hand into your deck without the use of a card effect.
• Shuffling your Prize cards into your deck without the use of a card effect.
• Shuffling your discard pile into your deck without the use of a card effect.
• Picking up your cards before both players agree on the game winner.
Recommended Starting Penalty:
Tier 1: Game Loss
Tier 2: Game Loss
I've given the Major penalty once. I've seen the Severe penalty once. This is probably more common than I want to admit. Most times neither player will call the judge for this problem, even though they should. Players are afraid of the game loss. Be careful