Sic stantibus rebus, to move Mark after the 135 CE, there is not even need of assuming *Ev priority.
Hermas is a 'mythicist' text, by logical implication.
This Couchoud's argument corroborates what we already know thanks to Earl Doherty (Jesus: Neither God Nor Man, pages 270-272):
Hermas treats the "church," the body of believers, as a mystical entity. It is God himself who has created the church (Vision 1, 1:6), including its pre-existent prototype in heaven. There is constant reference to the "elect of God," with no tradition about a church established by Jesus. Nothing which could fit the Gospel ministry is referred to. The writer can speak of "apostles" but never associate them with an historical figure who appointed them; there is no tradition of anything going back to such a figure. Instead, "apostles and teachers preach the name of the Son of God" (Parable 9, 16:5), in the same way that Paul and other Christian prophets preach the divine Christ.
The central section of the Shepherd discusses a great list of moral rules, some resembling the teachings of the Gospels, but no attribution is made to Jesus. A passage in the Fifth Parable (6:3) has the Son "cleansing the sins of the people," but this precedes his "showing them the ways of life and giving them the Law," and the former is never presented in terms of sacrifice or atonement. The 'giving of the Law' is through spiritual channels, for a later Parable states that the angel Michael (who in Parable 9 is yet another figure equated with the Son of God) has "put the Law into the hearts of those who believe." There is no preaching by an historical Son in evidence anywhere in this work.
In the same Fifth Parable, scholars think to find a reference to incarnation (verses 5-7) by making a link between the Son and "the Holy Spirit (which) God made to dwell in the flesh which he willed." But this link is not an obvious one, and in fact the text shows that the "flesh" in which the Spirit was sent to dwell does not refer to the Son, but to believers, who do not defile the Spirit while it dwells in them; that "flesh" is given a reward in heaven ("all flesh in which the Holy Spirit has dwelt shall receive a reward if it be found undefiled and spotless"), which is hardly a reference to the Son himself.
This writer is rooted in Hellenistic-Jewish mythology with its picture of a heaven in which different forces form part of the workings of divinity. The Son is one of many figures in a class photo which includes the Holy Spirit and angels of several ranks, and these are occasionally allowed to merge into one another. As Charles Talbert puts it (op.cit., p.432), "the Savior is described basically in terms of an angelology which has coalesced with the categories of Son and Spirit." The word "category" is apt, for Hermas is dealing with philosophical concepts here, not an historical figure who was God's incarnation. Had he possessed any idea of the Son as a human personality who had walked the earth in recent memory, suffered and died and resurrected outside Jerusalem to redeem humanity, he could never have buried him in this densely obscure heavenly construct and allowed the entire picture 'recorded' in the Gospels to evaporate into the mystical wind.
(my bold)