I've noted elsewhere that family is important in the Rice household. I have no idea exactly what Kaiden is looking for, but the desire of his parents is pretty obvious. Distance driving from Columbia, SC to Mobile, AL is a little under 8 hours (538 miles) in the totally opposite direction of where Tyler is playing. Distance to Williamsburg is about 6 hours where they can make a nice weekend out of seeing both boys. Of the top 8, no school is closer than W&M. I also put more stock into the input from Columbia area coaches and trainers that mentored Rice on his way up. Seems some of them are excited about the idea of teaming with his brother.
It's possible that Kaiden is swooned away during a visit to Alabama (nothing scheduled that I'm aware of), but IMO it's a local high major or W&M left standing at the end. Just makes too much sense with logistics, style of play, grad school opportunities, and needs of the program. South Alabama might be amassing transfers and a fun pick, but it is completely an outlier. If the NCAA tournament is his goal, then Loyola Chicago should be a strong contender. I think they were the only one in the 8 to make the field this year.
I have noticed a late comer in his follows - Coastal Carolina. Not sure if they are too late to the game, but proximity to home makes them an option.