Absolutely speaking, God can give Scripture knowledge without human ministry; Galatians 1
So the question is whether the Church's voice and testimony is needed to gain this knowledge. Briefly: absolutely speaking, no human labor is required for it. God can immediately, without anyone's outward ministry, give someone knowledge of Scripture and of his Word, and impress sure faith about it.
So Paul had not received the Gospel from a man, nor been taught it; he received it through the revelation of Jesus Christ, as he himself testifies (Galatians 1). So the other Apostles were led by the Spirit Paraclete into all truth with no man going before. So of old the Prophets learned from the Holy Spirit alone, who inspired them, what they spoke.
Latin
XVI. Quaeritur ergo, Num ad hanc notitiam adipiscendam opus sit Ecclesiae voce et testimonio. Breviter respondemus, absolute loquendo, ad hoc non esse necessariam ullius hominis operam. Siquidem Deus potest immediate, et absque cujusquam externo ministerio, alicui, Scripturae et verbi sui cognitionem dare, et certam de eo fidem imprimere. Ita Paulus Evangelium ab homine non acceperat, neque edoctus erat, sed per revelationem Jesu Christi, sicut testatur ipse Galat. 1. Sic reliqui Apostoli a Spiritu Paracleto ducti fuerunt in omnem veritatem, homine nullo praeeunte. Sic denique olim Prophetae a solo Spiritu sancto, qui eos inspirabat, didicerunt quae proloquebantur.