Upvote:3
Having been a Mennonite for all my adult life, and attending a Mennonite Brethren church for the last 8 years or so, I have never heard of The Shepherd of Hermas, or any of the other books you mentioned.
However, Mennonites, and many other denominations, often use written resources in sermons, corporate worship (recitations, hymns, songs), etc, that are extra-Biblical.
The official stand of the U.S. Mennonite Brethren Church on the use of such teachings is summed up in Article 2 of the Confession of Faith:
The Holy Spirit continues to make God known to individuals and the church; this revelation is always consistent with the Scriptures.
According to this, any extra-Biblical teaching which claims to be revelation of God ought to be permitted, so long as it is consistent with the Scriptures.