Are gallbladder vasculitis and hashimoto's disease related? should i look further or could that be two separate and unrelated things?

No relationship: I have never heard of gallbladder vasculitis, it must be very rare. Hashimoto's thyroiditis is an autoimmune disease of the thyroid. Although it can be associated with other autoimmune diseases such as vitiligo, pernicious anemia, addison's disease, type 1 diabetes, rheumatoid arthritis, etc., I have not heard of a correlation with gallbladder disease.

In a way: They are not directly related except that both are autoimmune diseases. Vasculitis of the gallbladder, particularly the cystic artery, is a rare complication of polyarteritis. See a rheumatologist if you have not done so already.