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

"This Digimon has [EX3-013]/[Chaosdramon] in its digivolution cards. and then an effect attempts to delete it. Is it possible to first activate this card's ""When this Digimon would be deleted, trash the top card of your opponent's security stack"" effect, trashing a security card from the opponent's security stack, and then activate [EX3-13]/[Chaosdramon]'s ""you may trash 2 level 5 cards in this Digimon's digivolution cards to prevent it from leaving play"" effect and prevent the deletion?"
Yes, it is.
Ruled Mar 28, 2024
When this card digivolves from [EX3-013]/[Chaosdramon], it gains all of the effects of the [Chaosdramon] in its digivolution cards. Does that mean [EX3-013]/[Chaosdramon]'s <On Play><When Digivolving> effect activates?
Yes, it activates. This card's ""This Digimon gains all effects of [Machinedramon] and [Chaosdramon] cards in this Digimon's digivolution cards"" effect is an <All Turns> effect, so it is active as soon as the digivolution is confirmed. Therefore, the <When Digivolving> effect is gained and triggered.
Ruled Mar 28, 2024
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