2 official rulings from Bandai, last ruled Mar 28, 2024. Straight answers to how this card actually resolves.

Does "for every 5 cards in both players' trash" mean for every 5 cards in either mine or my opponent's trash?
No, it means every 5 cards in yours and your opponent's trashes combined. For example, if you have 12 cards in your trash and your opponent has 8 cards in theirs, that makes a total of 20 cards, so the play cost is reduced by 8.
Ruled Mar 28, 2024
When an "Add 1000 to the maximum your DP-based deletion effects can delete" effect has activated, does this card's <On Play><When Digivolving><When Attacking> effect become "Delete 1 of your opponent's Digimon with 7000 DP or less. If no Digimon was deleted by this effect, delete 1 of your opponent's Digimon with 14000 DP or more"?
No. "Delete 1 of your opponent's Digimon with 6000 DP or less" becomes "Delete 1 of your opponent's Digimon with 7000 DP or less," but 13000 DP isn't the maximum for "delete 1 of your opponent's Digimon with 13000 DP or more," therefore it isn't affected and remains as "delete 1 of your opponent's Digimon with 13000 DP or more."
Ruled Mar 28, 2024
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