But this sentence is internally inconsistent. Before the comma it does refer to a roll of only two dice. But after the comma it refers to the same roll and speaks of "includes".
Now the sentence contradicts itself, a grammatical explanation it's not possible. Enter common sense to imagine what was intended.
I feel your pain non-high-elf players, but enforcing this easter egg restriction finds no basis in the rules.
(I'm no HE player either though)