In this much all the accounts agree. But scholars often lack the delicacy to think about these matters with the proper objectivity. For instance despite the alleged 'hostility' to the law and the prophets shown by the Marcionites Tertullian concedes that they themselves depended on the Pentateuch and its description of "the Creator's angels ... when in converse with Abraham and Lot were in a phantasm, evidently were of putative flesh, and yet really met with them, and partook of food, and performed the task committed to them." (ibid 3.9). In other words, there was an underlying compatibility with Judaism and its most sacred book throughout the supernatural understanding of their gospel.
The revelation of the gospel might have represented the end of the Law but no more than a digital music player represented the eclipse of a phonograph record. The underlying idea what that the time of the Law had come to an end. This certainly offended those who zealously clung to old ways. However it can't be coincidence that the gospel is understood to have been revealed in an age which saw the end of the sacrificial religion of ancient Israel. The Marcionites offered those proselytes who had recently come over to Judaism a solution to the coming to an end of the old way of worshiping God (ibid 3.21). What they proposed may have been a radical solution, one which 'offended' many people including Jews, but it was nevertheless a essentially a 'Jewish' solution in some sense.
In spite of the consistent reporting of 'hostility' against 'the Jewish god' it is important to recognize that there is a consistent recognition of Jewish principles of scriptural exegesis. The messiah who is to come will be as the Jews imagine him to be. Jesus is not the Christ. He is instead a wholly divine figure called 'Chrestos,' one of two powers of god, the embodiment of mercy who is wholly separate from the bloodthirsty military general predicted by the Law and the prophets. Rather than being a wholly unknown god, this merciful power was well known to contemporary Jews; who they seemed totally unaware of, by contrast, was the heavenly Father.
Indeed the ancient critics confounded two competing notions of 'secrecy' in the original Marcionite system. There was the Father who had always existed in heaven but was ignored in traditional Jewish worship and then there was the suddenness of Jesus's appearance at the beginning of the gospel - the failure of contemporary Jewish leaders to recognize who he was. It is impossible not to see that there was a deliberate irony here. The Marcionites were making a point clearly, that the Jewish leadership had 'lost sight of' or failed to recognize mercy (= Jesus). But this is certainly not the same thing as saying that the god Chrestos was an unknown commodity among contemporary Jewry. Scholars it seems have great difficulty seeing the poetry in the original gospel paradigm.
The failure of the Jews to recognize the angel of mercy who visited and communed with their Patriarchs was a deliberately cultivated irony on the part of the first evangelist. We have simply learned to read our gospels badly in what approaches now, almost two thousand years since Marcion.