You can't say, ... with any certainty, ... whether Paul had prior knowledge that his and other Apostolic writings would be canonized as scripture or not.
I just did.
In that case, ... what evidence do you have to support your claim ?
St. Paul was writing to Timothy in the example you gave, not the Church as a whole. It was not his intent to write Sacred Scripture; it was his intent to instruct and admonish Timothy, a bishop of the Catholic Church.
While Paul's motive in writing to Timothy is is to be considered, ... I believe that one might also consider the purpose of God.
God inspired Paul to write ...
... and, quite obviously, God intended that Paul's writing be canonized into scripture at the appropriate time.
Logical fallacies are a problem for everyone, believer or not. You'll never convince anyone of the truth if your argument doesn't hold water.
Our contentions on this point are identical.
God inspired the writings canonized in the New Testament.
God inspired the church to canonize the collection of the writings of the New Testament.
The church (through the inspiration of God) declared the New Testament writings to be scripture.
If there are any logical problems with this presentation, ... you and I share them.