How to split stems the best?

I'm working on a backing track right now for this song https://youtu.be/HMwwTpESuLM? si=ql2f8S_19RS507yp , so I need to split the stems. Those AI stem splitters don't split for example the keys from the synth leads and other synth stuff, so they don't give the results I need. Any tools in Ableton that could help me?