Yeah, FGO doesn't paint a good picture at all past "Voyager is a young Heroic Spirit that is in Chaldea and get stronger from there".
It doesn't help that not only is Fate/Requiem on hiatus, but the actual Erice is in Chaldea doing her own shit and even she's doesn't have the best picture past her lance being fake and how strong her spirits are... sorta.
EDIT: @Type-Rey Yeah, you are right, the game explicitly states that while Surtr is a perfect recreation, he's still a far cry from the Surtr we fought in LB2. So the same should be the case for Ivan too.
The body is similar, but the sword is a fake
fan translation because I cba to read this event twice