The EVA foregrip isn't an integral part of the rod and you won't do any functional harm even if you removed the whole thing; just don't scratch or scorch the blank itself while you're attempting any repairs. If you want it to look good you can cut a chunk out, neatly, where the hole is and use foam glue or contact cement to fill the hole with a matching plug of foam. You may even be able to find a small (thumbnail sized) foam football, baseball, a different colored piece cut to the shape of a lightning bolt, or whatever suits you to use as a plug and add some customization; just neatly cut your chunk out to match the size and shape of the plug. EVA will cut easily with a razor blade or sharp exacto knife or you can dremmel it and it's compressable enough to fit snugly into a "near enough" hole. You can buy foam sheets at a local crafts store and they may have foam icons that would add class or humor.