Is tribal affiliation (and/or Ashkenazi/Sephardic status) passed on by a non-Jewish father?

I’m asking this question mostly from a Masorti/Orthodox perspective, but I realize opinions may differ considerably.

Long story short, my mother is Jewish (and so I am Jewish), but my father was not. I recently learned, however, that my great-grandfather on my father’s side (direct patrilineal line to me) was Jewish. My mother is Ashkenazi, but my great-grandfather (father’s grandfather) was Sephardic. My questions are:

1. Was my great-grandfather’s tribal status passed down to me patrilineally, despite my father and grandfather not having Jewish mothers?
2. Should I (or could I justifiably) be following Sephardic minhag?

I was not raised in a formally religious household–during most of my childhood my mother was agnostic-ish while my father was loosely a Sufi heavily influenced by Taoism and Buddhist and Hindu mysticism, among other things. Later on in life, I’ve become more interested in Judaism, but I’ve oddly always been drawn more to Sephardic minhag as opposed to the Ashekanzi customs from my mother’s side of the family, despite the fact these are ostensibly the traditions I “should” be following.

I’ve always had it in my head that my interest in Sephardic traditions was thanks to my father, who was, to my knowledge, ethnically a mix of North African, West African, and Portuguese, among other things. I now wonder, though, if there may be some halakhic basis making it permissible (or even obligatory) for me to follow Sephardic customs.

Obviously I’m just looking for an excuse to eat kitniyot and soft matzah this Pesach. Just kidding. Mostly.

All jokes aside, I’ve tried researching this a bit and haven’t been able to find much. I know there are some pretty knowledgeable people who frequent this subreddit so I’m curious to hear if anyone has any thoughts.