The thing is, let's forget that it's Yzerman and make it any generic GM (lest I be labeled an Yzerdrone). That would be an inexplicably incompetent move by any general manager in the NHL. We're not talking about overvaluing a player or making a bad trade. This is not bothering to reach out to anyone else before pulling the trigger on an unfavorable deal.
Which is why I find it hard to believe that's the case. Even if a GM were insanely busy, he could easily have their assistant GM or VP of Hockey OPs reach out. It's a pretty small world still.
I find it more likely that either that it's being overstated GM's were surprised, or that there is a significant missing piece to this puzzle.
Unless Yzerman developed a substance abuse problem (insert weed joke here), I don't see how he fails to do something so basic unless it's for a reason.