Hello,
I've just finished the game 100% and don't think this would work. There isn't a fixed amount of Kocos in the game to collect as you can get them through the various fishing spots on the island. When you reach the final island, you can buy an infinite amount of Kocos with the game hard capping you at around 5463 Koco. It will let you buy more but, it won't add to your counter. I think it was designed this way so people are able to get the 4 achievements 4 speed, rings, attack and defense.
The only way I can see it working is collecting the EXACT amount needed to upgrade Speed/Rings but even then, it'll likely just be fast to speed through everything to get to the 5th island then go fishing due to fishing here giving you a large amount of tokens for most catches here.
In my experience, I was collecting them along the way but, also buying them at fishing spots. When I got to last island to fish, I hit the hard cap after burning tokens. Once I was done upgrading, I still had 4300 Kocos left in inventory.
So just to be clear, I can still keep using livesplit as I was, correct?