u/DraconKing

There's evidence that might support it:

It's previous user was referred as the Warrior God of Elbaph. Elders are also referred as Warrior Gods. However it does seem to be using different japanese words for both instances. Looks like Elbaph God of War is written as "Ikusagami" and on each instance for the elders they used the word: "Bushin".

Disclaimer: I don't know japanese but I used the AI to help me translate the kanjis.

Another hint can be that he initially opposed Nika. Just like an Elder would in todays age. Presumably he would change sides after this encounter?

Lastly, Imu called him a Traitor. This means the previous Nidhogg user was probably an ally of Imu.