Just need advice here. I wrote a song and collaborated it with a vocalist and a producer. I sent my song to the produce then he sent it to the vocalist of which we know each other well.

Now, I asked another friend of mind to listen to the song and he said he liked it and want to do a remix of the song, so I ask the producer collaborated with to send over the vocal stem to me so I can send it to my friend to remix it but to my surprise he do not want to send me the vocal Stem. He said the vocalist will have to agree and she do agree. He talk about the % spits of which everyone agreed.

So I am wondering what is the big deal. Should I ask the vocalist we collaborated with for the vocal stem?, I need your help.. .