He was never SIGNED to Star Trak...he was SIGNED to Geffen. You don't have to be signed to a label to put out an album with him. In the R&G case, instead of Pharell getting most of the money up front for tracks, the deal was that he would put his label imprint on the album and get more points off the album. The only time Snoop ever considered signing to Star Trak was before and during the Capitol situation. I was working at Capitol at the time and the Paid the Cost to Be the Boss album was one of my projects there, so I know that the negotiations started, but nothing ever happened.
