Ok so I know i am revisiting this, however i could not find any solution myself using the suggested fixes and via documentation and research. I recalculated all normals in blender, redid the UV maps as best I could, played with all export settings and import settings.
this was the only thing i was able to do to mitigate the majority of the literal holes in the mesh (symmetrical and on the side not shown)
I have never ran into this before and i only get it with this particular model
in the static mesh details, in Build Settings, enabling the “Use High Precision Tangent Basis” and hitting apply, solved like…95% of the problem.
in second image on the rear quarter panel, there is still a small hole. however i can work around that for my purposes.
i tried playing with setting combinations in various ways and could not find any way to remove the remaining quarter panel holes
**you will also notice the wheel well somehow got choppy. and fiddling with the “recalculate normals” function does affect it minorly, however that is the only thing that is visible currently that got negatively impacted by this process, and since it is behind the wheels, it is not of concern currently
hope this helps someone in the future or my own future self