With thanks to Pro Hockey Talk's Mike Halford for the find
Well I guess that clears up a least a little bit of mystery.
The 25-year old Emmerton just finished the last year of his first post-ELC contract, which gave him a league-minimum cap hit and expires with him as a restricted free agent. He played just 18 games with the Wings this season, putting up 2 points in that span, but was able to put up 46 points in 53 games during the regular season in Grand Rapids and add another 9 points in 10 games for the Wings' AHL affiliate in the playoffs.
Grand Rapids' playoffs ended Sunday with a 7-1 loss in Game 6 of their series against the Texas Stars.
Detroit wasn't likely to tender Emmerton a qualifying offer which would have granted them the ability to keep his rights as a restricted free agent and the prospects that he was going to find an NHL team with which to sign were pretty slim after he wasn't picked up on waivers during the season, despite having literally a small a cap hit as is possible under the CBA. Whether he waited until July to officially become an unrestricted free agent or not probably doesn't matter.
Personally, I always kind of liked Emmerton. He wasn't skilled enough to grab onto a full-time NHL position, but he always seemed to have a good attitude. That's the least anybody could ask of a guy in his position. I'll wish him well in the KHL next season.