I lean towards IEI but could see why people are saying SEI. Your initial vibe is very positive and Alpha-like, and the talk about valuing family and moving to be near your grandparents sounds exactly like what the SEIs I know would do.

Points for IEI:
-The fantastical inner world you described imagining since childhood. None of the SEIs I know (and I know several very well, including my mom) have ever described constructing anything like that. My SEI roommate once said, "I was not an imaginative child." Not to say SEIs are all unimaginative, of course, but I would think even an SEI-C wouldn't be so involved in an abstract fantasy life. Their Creative subtype would manifest more in the physical world.

-Predicting outcomes for others around the 7:40 mark in the second video. SEIs can give really good and wise relational advice but I rarely hear them warn about the future like "if you do this, then this could happen."

-Positive, cheerful presentation could be related to enneagram type and instinct, not just quadra. Not all IEIs are moody type 4s

Regardless of your type, glad you're around!