Detroit makes sense as an eventual destination, but I don't see him having any interest in waiving for them this summer. They may be on the rise, but they aren't yet in the ballpark of actual contenders yet. They finished with 74 points and a -82 goal differential.
But more importantly, most of the roster are still just seat warmers until their prospects and young players actualize. Fabbri is the only player on the roster under contract beyond 2023/24 and the bulk of their veterans become UFAs a year from now (Larkin, Bertuzzi, Suter, Sunny, Erne, Gagne, DeKeyser, M Staal, Oesterle, and all the goalies hit UFA either this summer or next).
That team is still multiple years away from competing in the playoffs. There is little incentive for Krug to waive his NTC to go from being a top 4 guy on a top 10 team to go to a team that is still midway through a long-term rebuild.
I cold see him waiving to go there in a couple years when they have actually risen into and through the middle of the pack (and we are potentially fading in the other direction). But that's a couple years out.