By owners do you mean the person who made the mp3, or the artist and recording company responsible for the music itself?
Cause if you don't mean the artists and recording companies, then the person who made the mp3 is violating copyright too.
Now if you do have the artists and recording companies permission for this, then they would've given it to you in legally-binding written documents detailing such, and likely required you to have a lawyer present to verify the document was legitimate. If you have this, we can figure out a way for you to send a photocopy of it for verification purposes, but without it there is nothing to discuss.
Edit: I should note that "companies" is plural as is artists because there is more than one artist and more than one recording company represented in your music collection. Every single one must be properly licensed for redistribution or they're illegal.
If any one is illegal (and right now they all look the part), then the account is permanently suspended, no access provided in conjunction with sections 6 and 8 of the terms. Section 8 in particular details the forfeiture of all rights to files/databases on account when suspended for contravening the terms.
