A band of a friend is releasing their debut album next month, and now (march 3) they have a digital single on Spotify released through the record label, does it qualify for submission?

On its own, no.

If you're looking to get a band accepted based on a digital release, it should be a finished, professional, quality album with around 20 minutes of metal music made available in full as a band-sanctioned download. As Diamhea pointed out, a digital single (especially one released via Spotify) would not be enough to meet these requirements.