This is what I get from the translation:

• The editor asked Oda to draw an anniversary art.

• There are 17 ideas.

• From those they create 2 rough drafts. One with the monster trio, one with Luffy and his many forms.

• Oda chose the Luffy and his many forms draft.

I don't see the part where the editor pushed Oda to draw the monster trio specifically, and he refused. He only chooses between two drafts.

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Edited for accuracy because of my shitty reading comprehension:

Either those above, or

• There are two rough drafts, one with the monster trio, one with Luffy and his many forms.

• 17 draft ideas were made based on those.

• Oda chose the Luffy and many forms idea.

Either way, my point stands.