Since adding GTW

I know it sounds silly but have you tried deleting the toilet in game and buying a new one? My Sims done that with the fridge, they wouldn't use it but I deleted it and brought them a new one and then they used it. Might be the same with the toilet?

if  you have mods/cc a lot of them where broken with the patch move the mods/cc folder to the desktop launch your game and see if it works