Interesting, I never asked a question, but true to form, you answered a non existent question. James is writing to Jewish believers who are under the same Gospel as Gentile believers. They both were concluded under sin by Paul in Romans and both receive the gift of eternal life as a free gift by faith. Your distinctions are bogus, and amounts to another Gospel which Paul also warned against in Gal 1:6-8.
What is GOK and GOG?
Protestants don't ignore John 20:23, Lutherans use it all the time in Confession and Absolution. That is used to give the 'priest/pastor authority to absolve others of their sins.
The typical condescending line. There is no contradiction, but for the reasons I had mentioned earlier. It has nothing to do with who was being addressed.
There is no distinction between Jew and Gentile in soteriology, for ALL (both Jew and Gentile) have sinned and are shut up unto Judgment but for the grace of God found in Jesus Christ.
Methinks you need to set aside that twisted views of yours, they definitely are not classical dispensational teachings and all in all preach a different Gospel to the Jew and Gentile.
But contrariwise, when they saw that the gospel of the uncircumcision was committed unto me, as the gospel of the circumcision was unto Peter; (For he that wrought effectually in Peter to the apostleship of the circumcision, the same was mighty in me toward the Gentiles
And when James, Cephas, and John, who seemed to be pillars, perceived the grace that was given unto me, they gave to me and Barnabas the right hands of fellowship; that we should go unto the heathen, and they unto the circumcision.
(Gal 2:7-9)
These aren't speaking of two different Gospels but two different directives given to two different messengers (Paul and Peter).