If you have created a new composition or derivative work and just intend to upload it for non-monetized, non-profit promotion then yes, you need to include a link to https://freevocals.com in the track description.
You only need permission from us if you do want to feature a vocalists name in a non-monetized, non-profit track title. Request permission here – freevocals.com/licensing
If you don’t feature a vocalists name in your track title and do include a link to our website in the description, then you don’t need permission to upload a non-monetized, non-profit track.