Yes, Vang Christensen is the Danish 18-year old. Feels strange to say his result is the least impressive of these.
Øyen's progression doesn't seem to be lagging Jakob's all that much - he's run 3:46.96 and 8:10.07 earlier this year for the 1500/3000, the 3000 merely days after he turned 16. He's also somewhat "ahead" of 2021 Laros (Edit: for the 3000 and up).
As for Torbiörnsson's performance - her performances are not to dissimilar to what Bjerkeli Grøvdal ran at that age. (Both Øyen and Torbiörnsson have WA profiles).