Sorry, I do have much experience in discord, maybe this link will work fine :) https://discord.gg/mAypdfVP There - project diva controllers discussion
Update: Got help from the discord server, turns out i really needed to trick the game to think I'm using a HORI project diva controller. After updating my VID/PID, the slider started working. Thanks for the help!
That's good. But I thought that could be much simpler. But maybe in case of using Arcade mode in game - yeah, if I understand right.