I totally agree with you, he could not make RBY do want he wanted them to do so he walked. No insider trading concerns with that decision. He has done this in the past like you said just ups and sells out. 3rd world countries are no good ask KRY. His selling is a windfall for those that know that nothing about the company has changed except for a major shareholder leaving because he didn't get his way.
McEwen is not coming back to RBY. I think that speculation should die. If he wanted RBY in any way he would have kept his shares. Why would he create a taxable transaction if he was coming back. He is just walking away to do his own thing. He is satisfied with 4.16 Canadian minus costs of selling less taxes on his huge gain.