After I know this how could I leave the church?

[Mister Agenda]

Bibliofagus, one of the 'rules' of canonisation was that they must have been derived from apostolic times or earlier, and they must have had use in the church's liturgy. But it's worth also noting the early Church had a high view of other writings, such as those of the church fathers, or the Didache. It is perhaps a little anachronistic to look back at other early writings with post-Reformation eyes.

Your reasoning is sound, but lack of such documentation, while understandable, is a problem for corroborating what actually happened.