In my opinion, the FV is not as high-profile an issue in the OPC. At one time, it seemed to be there because it was conflated with some other issues that were disturbing the church re. justification.
There are other issues which also seem to tie-in with FV, at least in the minds of some. Because FVers are often (though perhaps not exclusively) theonomist, if someone self-identifies as a theonomist he might be suspected of FV sympathies. But it should be recalled that the RPCUS (Morecraft and Co.) are theonomist, and blew the whistle on the FV (Wilkins, Auburn Ave, etc.).
This only makes it clear that the subject needs to be studied and critiqued narrowly, and not broadly, lumping-in other positions that do not deserve the same discredit. This was one aspect of the OPC GA appointed study-committee on FV that was quite good. It was a focused critique, and it answered the specified question (re. justfication) by contrasting the historic, biblical and confessional position with at least two modern recastings: NPP and FV. While no prophylactic endures forever, the present state is one in which the inoculation provided seems to be keeping FV-cancer "in remission" in the OPC.
For better or worse, the OPC is seen by outsiders already as a group too-homogeneous and too small to "matter" on a stage for greater influence; as well as too-beholden to "old guard" leadership, which changes slowly and from within. The OPC is too "historically self-conscious" to instinctively or uncritically view its identity as "inclusive." So why should FV "target" the OPC, when even if it were successful (quite unlikely at this moment), FV would still have little more influence on "culture" than does the RPCNA or the RCUS (both also small denominations).
The PCA is theologically fissiparous (in fact, if not on paper), and its big-tent mentality grants a degree of wiggle-room to innovations. There is irony here. The OPC is both less top-down controlled, and more homogeneous; while the PCA has developed a centralized bureaucracy (complete with "visionary leadership"), and a factional constituency. Is this just the "price" one must inevitably pay for numerical growth and financial clout?