Well, CFD seems to know that those fish look like, njsconst . I'm quite sure that these long, eel-like prey items are often juvenile scabbardfish/ribbonfish (Lepidopus caudatus). The adults of this species appear incredibly similar to hairtail (excepting, of course, the filamentous tail). Here's a pic from fishbase:
The juveniles vary in morphology:
The likeness to hairtail might explain why you thought that the fish were juvenile hairtail, njsconst. Oarfish don't have teeth - hence the name "king of herrings" that is often applied to these massive fish.
Hope this helps,
Flattieman.