[Snake]

Honestly, letting them be there but removing their Immortality would be enough.

An explanation could be them being a different form of Vampire, one not made from Huggessoa but some ancient curse or disease, like The Elder's Scrolls one.

This would at least let us have a baseline non-godmade Vampire in our lore that is always 100% antagonized and seen as a threat if discovered or denounced. It would add to the general lack of action that we can suffer sometimes.