The theme that runs through the whole “suffering servant” cycle John 12:41 mentions is “glory.”
So a paraphrase would be something like…
Thus, Jesus rightly says “Abraham rejoiced to see my day.” John 8:56.
Again, nothing to do with a literal, pre-existent person; let alone the 2nd member of a 3-in-1 God!
Also of note is the identity of “the servant of Yahweh” as originally the nation of Israel itself (Isa 41:8; 45:4; 49:3, a preexistent being?!)! And the nation is portrayed as a suffering, human being called:
Nonsensical, not to mention blasphemous, to somehow read this figure as Yahweh Himself!