One of my collegues does 3d design but I am not sure about the not paying part.
Telling a 3d artist that he is not going to be paid for his long hours spent prepairing your design for you and that he will have 70% freedom and it will bolster his portfolio is going to draw out a lot of timewasters and leave the good ones not interested.
Suppose it depends on how much your team are depending on this.
I am sure he will do it a bit cheaper and you could always email him and ask.
Check my logo design sig in my link, you never know, catch him on a good day and you may even get your wish
