Here are some areas to compare and contrast, and perhaps if we place them in a table of comparison it would become more clear:
-----Ancient Skepticism vs modern notion of skepticism, vs aspects of "skepticism" in modern science vs Epicurean canonics, AND for each one what level of "feeling" of "knowing truth".
Is it possible that there were differing takes on the sense of knowing (and level of belief vs faith) within various groups of Epicureans (just like there were likely differing takes on mental vs physical pleasures)...it wouldn't be right to assume that all ancient Epicureans were "cookie cutter" exactly the same (thinking/believing exactly the same), because human beings are complex, and you can see now (in our modern studies) how we have the "minimalist" Epicureans and the "maximalist" Epicureans - so perhaps there was also some differences between levels of dogmatism (plus also levels of belief in the gods).