There was likely much revision in the second century. For instance, in 1 Corinthians 14, it seems the "women be silent" was an interpolation. And Paul never actually wrote 1 Timothy which says the same thing.
Of course, the New Testament is a compilation of books from different
Christian groups from the first and second century, each with different
theological viewpoints.
But from what Paul and the Christian group he was writing to
at Philippi, I think their answer would be found at Philippians 2:9, “Therefore
God exalted him to the highest place and gave him the name that is above every
name.”
Therefore the name above every name is given to Jesus...the
one who in verse 6, who had “God’s form” or nature.
No matter whether the LXX with the divine name was used by
the New Testament writers or indeed placed the name in their original writings, often passages
in the Old Testament that were about YHWH got applied to Jesus. For these
writers Jesus was by nature or kind YHWH, while a distinct person from his
Father.
The writer of the epistle of John would have agreed. Of
course, the writer of Mark would’ve bitterly disagreed. And likely the writer
of Matthew and Luke.
Whatever the original form of the writings that became the
New Testament and whether the Divine Name was included, or passages like in Philippians
were ramped up and altered to reflect high Christology is still speculation and
guesswork.
Until someone finds an early NT manuscript with the divine
name in it, there is no real proof.