You can veganize almost anything on passover, the only tricky items are on the seder plate and they're symbolic anyway, so we just replace them with different symbols. Funnily enough, most chicken soup powder / chicken stock doesn't contain real animal products.

If you really want to ask tough questions then riddle me this: outside of wishful thinking, how does anyone buy the idea that fish or eggs are parve?! And why is it that women who are menstruating are untouchable, but we're allowed to eat chicken menstruation?