TFTrue does work on windows (with the .dll), you don't need metamod and/or sourcemod to run it.
You'll know that you installed it properly if you see it mentioned in the status command (might need rcon status, I don't recall)
The download ZIP should contain the instructions, make sure you put the files in the right location, it's possible your provider doesn't let you access the right folders but that's unlikely
It should look something like Team Fortress 2 Dedicated Server/tf/addons/TFTrue.dll
It's also possible the Windows hooks are outdated, in which case you'll have to ask AnAkkk to update it
gl