RE: Anyone using VARTM?
A few years back, when I was involved in open-mold, wet layup manufacturing of carbon fiber automotive panels, one of the production guys got very good results by adding a small percentage of acetone to his epoxy resin mix, for the application of the first layer of CF, up against the mold surface.
At first, I didn't feel good about adding any acetone to the mix, but it did help with reducing the viscosity during the working period, and helped the resin clarity surrounding the C/F.
Have you tried this? My first thought concerning your situation, is that a lower viscosity resin might penetrate further, and you might also experiment with a slightly lower vacuum level, during the initial infusion stage, so the stack of fabric is looser, and then crank it back up, once the area is fully infused.