I think the primary reason for the change to Indian Ocean splashdown is because of the addition of the “deorbit” burn test. As for tracking assets… that’s a good question! It’s possible they’ll have a ship or something there, maybe they included a “black box” they expect to survive reentry, or perhaps they think they’ll get enough info from their massively beefed up starlink connections.

I also heard that they will reenter during night time. Might make it easier to see even with simple assets like a boat!

All this is purely speculative :)