Of course anyone can do anything. Dak has made it clear he is comfortable gambling on himself and playing out the year.
Translation = He will not be traded.
Teams can call around. GM Jethro can call around(doubtful) Fans on this site can continue to speculate, wish, hope, theorize all they want about Dak being traded.
Dak is not disgruntled. He has shown up to every event mandatory or otherwise. He is in good spirits. He is at peace with it. He has been in this situation before. Him and his agent asked for the no trade clause for a reason. I actually think Dak enjoys it. It is motivating to him.
If GM Jethro can't figure it out, Dak will be in a position to be the highest paid player in the NFL or have the opportunity to take less on a team he feels are ready to make a deep run.
Why would he not follow in Peyton Manning's footsteps in Denver, Tom Brady's footstep in TB, or what Aaron Rodgers is attempting to do in NY, while getting paid at the same time? And in this situation it would even be much better because his new team would not have to give up any picks.
It is not hard to figure it out. Maybe the reason GM Jethro had not signed Dak is because he can't. Every day that goes by, it is more likely that Dak wants to test Free Agency.
Dak and France are 1,000% in control of the situation. It is not personal, it is business, isn't that what Owners and GM's say all the time?