Nobody thinks the Pope is impeccable, only infallible in certain specific circumstances.
If you believe that the NT is inspired, you believe that, e.g., Peter and Paul exercised a higher gift than infallibility when they wrote Scripture.
I think you’re confusing “infallible” (able to teach without error) with “impeccable” (without sin).
Paul had a problem with Peter which you could say he told to the whole world of Christendom,
If Paul was right Peter was not impeccable.
If Paul was wrong Paul was not infallible.
Peter said he was chosen to give the word to the gentiles.
Paul said that he was.
Were both of them infallible?
I believe scripture is inspired by God but what was considered scripture in those days?
I doubt very much if Pauls letters were considered scripture at that time.
And i do believe that any thing any Church teaches that is not backed up in plain words by scripture has a good chance of being wrong.
Also of the many translations how many say exactly the same thing, they can not all be 100 percent infallible.
Infallibility is something i do not believe any one has except for God.