I'm not sure what you mean by "uncompromisingly responsible".
I take verses 13-16 that WE are responsible for warning others.
As for the second question, you will get different answers... this is often debated here.
My take is ...
In the old Testament.. only the Jews were God's chosen people. ( Deut 7:6; Deut 14:2; etc.. )
In the new testament, the Gentiles now have access to salvation (through Jesus).
But the house of Israel... is still only the biological sons (descendants) of Israel (Jacob).
We can now be called God's chosen people. 1 Pet 2:9; (although some contend Peter was only written to the Jews)
But Gentiles are not the biological sons of Jacob.
We need to be careful about saying we are. ( Rev 2:9; Rev 3:9; )
In the New testament, the phrase "the sons of Israel" is used 15 times.
In several of those places it is referring to the Jews of the old testament.
( Matt 27:9; Luke 1:16; Acts 7:23; Acts 7:37; 2 Cor 3:7; 2 Cor 3:13; Heb 11:22; etc... )
A couple of verses are talking about the 144,000 who are also from the sons of Israel ( Rev 7:4; Rev 21:12; )
In Acts 9:15; Luke says that Paul is chosen to bear Jesus' name before the Gentiles and the sons of Israel.
So obviously the sons of Israel aren't the Gentiles.
In fact.. it seems not all of the sons of Israel will be saved.. only a remnant ( Rom 9:27; )
So if the sons of Israel are all believers... then why would only a remnant of them be saved?
I really see no place in the new testament where Gentiles are called the sons of Israel.
The one passage that seems to cause some confusion here is in Rom 2:28-29;
But even here, it doesn't use the phrase "sons of Israel, it simply says "a Jew".
Jesus also seems to separate the house of Israel from the Gentiles. ( Matt 10:6; Matt 15:24; )
Who are the people of Israel today? What did Jesus say? Romans 2:28-29 (CJB)
28 For the real Jew is not merely Jewish outwardly: true circumcision is not only external and physical. 29 On the contrary, the real Jew is one inwardly; and true circumcision is of the heart, spiritual not literal; so that his praise comes not from other people but from God.
A true Jew, a true man of the house of Israel is one who lives the Word of God.
And yes robaston Ezekiel took full responsibility for his people. In fact if you read on, you will see that he was quite angry with his people right then. ... I think that's what you're saying?