Were Saints Justin Martyr and Pope Clement really Christians?

I am currently in the process of writing one of my most important articles on Sola Fide, and as I was doing some research I came across an astounding facepalm quote in a well respected Protestant dictionary. The TDNT speaking on imputation says this about Romans 4:3-8:

Justin Dialogue 141.2-3 rather misses the point when he suggest that repentance is the ground of nonimputation (cf. Faith in 1 Clem. 10.6).

This is a polite way of saying Saint Justin and Saint Clement totally misunderstood and botched a fundamental text of salvation (Rm 4:3ff). Upon tracking down those two quotes, I felt it worth making a short post about it.

Justin (Dialogue with Trypho, 141) But if the word of God foretells that some angels and men shall be certainly punished, it did so because it foreknew that they would be unchangeably [wicked], but not because God had created them so. So that if they repent, all who wish for it can obtain mercy from God: and the Scripture foretells that they shall be blessed, saying, 'Blessed is the man to whom the Lord imputes not sin [Rom 4:6-8; Ps 32];' that is, having repented of his sins, that he may receive remission of them from God; and not as you deceive yourselves, and some others who resemble you in this, who say, that even though they be sinners, but know God, the Lord will not impute sin to them. We have as proof of this the one fall of David, which happened through his boasting, which was forgiven then when he so mourned and wept, as it is written. But if even to such a man no remission was granted before repentance, and only when this great king, and anointed one, and prophet, mourned and conducted himself so, how can the impure and utterly abandoned, if they weep not, and mourn not, and repent not, entertain the hope that the Lord will not impute to them sin?  

Clement (Epistle to the Corinthians, 10) Abraham, styled the friend, was found faithful, inasmuch as he rendered obedience to the words of God. He, in the exercise of obedience, went out from his own country, and from his kindred, and from his father's house, in order that, by forsaking a small territory, and a weak family, and an insignificant house, he might inherit the promises of God. For God said to him, Get you out from your country, and from your kindred, and from your father's house, into the land which I shall show you. And I will make you a great nation, and will bless you, and make your name great, and you shall be blessed. And I will bless them that bless you, and curse them that curse you; and in you shall all the families of the earth be blessed. [Genesis 12:1-3] And again, on his departing from Lot, God said to him, Lift up your eyes, and look from the place where you now are, northward, and southward, and eastward, and westward; for all the land which you see, to you will I give it, and to your seed for ever. And I will make your seed as the dust of the earth, [so that] if a man can number the dust of the earth, then shall your seed also be numbered. [Genesis 13:14-16] And again [the Scripture] says, God brought forth Abram, and spoke unto him, Look up now to heaven, and count the stars if you are able to number them; so shall your seed be. And Abram believed God, and it was counted to him for righteousness. [Genesis 15:5-6; Romans 4:3] On account of his faith and hospitality, a son was given him in his old age; and in the exercise of obedience, he offered him as a sacrifice to God on one of the mountains which He showed him.

In other words, these Protestant scholars are saying Justin and Clement misunderstood Paul's teaching on faith alone, since they ascribed repentance and obedience as part of faith for justification. The irony is, if talk like this causes certain Protestants to say Catholics have denied the Gospel and thus are not Christians, then what does this make Saints Justin and Clement?