Hi, no I don't believe there is a way for someone to split usage from publicly available info.

You are right that it's now available to play without an XBot token.

So I went back to the data, and I just randomly looked up 10 of the 53 Tier 4 accounts in my dataset:

-7 have XBot tokens
-2 share XBot tokens across multiple accounts
-1 has an Archmage token

So 100% of the very small sample have access to a high quality service for free ranked battle assistance. I suppose they might want to pay occasionally but that doesn't seem likely to be the primary use case.