One thing worth considering is the Bundesliga and it's plan to become the best league in the world, with its perfect model blah blah blah.
They may be worried about the perception of the league if a Premier League team comes in and cherry picks it's Player of the Year. As how can it ever eclipse England if we come in and take the league's best talent? That might be why a sale to Bayern is more accepted in Germany? Obviously there are the board connections too and the general 'togetherness' of the Bundesliga, as corrupt as they may be.
Probably looking too far into it and KDB will be ours. But it would be strange if they preferred to sell to a rival as that would never happen over here.