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

When my Digimon with [Greymon] isn't affected by my opponent's Digimon's effects from this card's <Main Timing> effect, can it be blocked by an opponent's Digimon?
Yes, it can be blocked. <Blocker> is an effect that allows the Digimon with the effect to block, so it isn't affected by "isn't affected by the effects of your opponent's Digimon" effects.
Ruled Mar 28, 2024
When my Digimon with [Greymon] isn't affected by my opponent's Digimon's effects from this card's <Main Timing> effect, is it affected by <Security> effects on my opponent's Digimon?
No, it isn't affected. <Security> effects on Security Digimon are treated as Digimon effects, so the "this Digimon isn't affected by the effects of your opponent's Digimon" effect prevents such effects from affecting this Digimon.
Ruled Mar 28, 2024
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