From my experience, excess FFAs seem to be taken out by the gall bladder and excreted via the bile duct. The HF that I think you are referring to here is meant to be part of a ketogenic diet, and so the FFAs are supposed to be burnt off and turned into ketones unstead of using glucose for energy. the large amount od FFAs in the Mendoza article are probably packaged into chylomicrons and VLDL so are not actually free radicals unless the package is damaged during transit (sdLDL). Certainly experimental reports show that higher fat leads to these effects and the blood takes on a milky hue. In this form the body is doing exactly as it should, and it is not (so far) been shown to be dangerous. The liver only releases trigs from storage when glucose levels fall, i.e. ketogenic or starvation or fasting state, and it also needs an absence of insulin to do this..
Although we do not know exactly what causes IR, a ketogenic diet does show success in helping remission to happen, so if used properly, it should not increase IR as a long term effect. In fact, evidence has shown recently that increased fat intake actually improves the lipid panel for many if part of a low carb diet, The jury is still out on high fats with high carb diet.